Multimer forms of acylphosphines and their derivatives

ABSTRACT

Compounds of the formula (I), in which E is O or S; and x is 0 or 1, A is cyclopentyl, cyclohexyl, naphthyl, biphenylyl, anthracyl or an O-, S- or N-containing 5- or 6-membered heterocyclic ring, where the mentioned radicals are unsubstituted or substituted by halogen, C 1 –C 4 alkyl or C 1 –C 4 alkoxy; or A is a group formula (II) R is C 1 –C 24 alkyl, unsubstituted or substituted, C 2 –C 24 alkyl which is interrupted once or more than once by nonconsecutive O, S or NR 14  and which is unsubstituted or substituted, C 2 –C 24 alkenyl which is uninterrupted or interrupted once or more than once by nonconsecutive O, S or NR 14  and which is unsubstituted or substituted, C 5 –C 24 cycloalkenyl which is uninterrupted or interrupted once or more than once by nonconsecutive O, S or NR 14  and which is unsubstituted or substituted; C 7 –C 24 arylalkyl which is unsubstituted or substituted on the aryl group. C 4 –C 24 cycloalkyl which is uninterrupted or interrupted once or more then once by O, S or NR 14  and which is unsubstituted or substituted, C 8 –C 24 arylcycloalkyl or C 8 –C 24 arylcycloalkenyl; or, R is a group of the formula (III) W is a bond, —CO—O— or —CO—N(R 15 )—; L a di-tri-or tetravalent linking group, n is a number of 2,3 or 4;

The present application relates to dimer and multimer forms ofacylphosphines, acylphosphine oxides and acylphosphinesulfides to thepreparation thereof, and to the use thereof as photoinitiators.

E. Lindner et al describe in Z. Naturforschung, B: Anorg. Chem., Org.Chem. (1978), 33B(12), 1457–60 dimer forms of acylphosphine oxides asfor example 1,2-ethanediylbis-benzoylphenylphosphine oxides with respectof their behavior towards molecular oxygen.

The German Patent Publication DE19618720 describes bisacyl-bisphosphineoxides as for example1,2-bis(2,4-di-pentoxyphenyl)-1,2bis(2,4,6-trimethylbenzyol)diphosphineoxide being useful in photopolymerisable compositions.

It has now been found that dimer and multimer forms of acylphosphines,acylphosphine oxides and acylphosphinesulfides as described below showan improved curing behaviour due to additional crosslinking andfurthermore, contain less volatile decomposition products and byproducts than known acyl- and bis-acylphosphine oxides.

The invention provides compounds of the formula I

(I), in which

-   E is O or S and x is 0 or 1,-   A is cyclopentyl, cyclohexyl, naphthyl, biphenylyl, anthracyl or an    O-, S- or N-containing 5- or 6-membered heterocyclic ring, where the    radicals cyclopentyl, cyclohexyl, naphthyl, biphenylyl, anthracyl or    O—, S— or N-containing 5- or 6-membered heterocyclic ring are    unsubstituted or substituted by halogen, C₁–C₄alkyl or C₁–C₄alkoxy;    or-   A is a group

-    wherein    -   R₁ and R₂ independently of one another are C₁–C₂₄alkyl, OR₁₁,        CF₃ or halogen;    -   R₃, R₄ and R₅ independently of one another are hydrogen,        C₁–C₂₄alkyl, OR₁₁ or halogen; or    -   two of the radicals R₁, R₂, R₃, R₄ or R₅ together form        C₂–C₁₂alkylene, which can be interrupted by O, S or NR₁₄;-   R is C₁–C₂₄alkyl, unsubstituted or substituted by C₃–C₂₄cycloalkyl,    C₃–C₂₄cycloalkenyl, phenyl, CN, C(O)R₁₁, C(O)OR₁₁, C(O)N(R₁₄)₂,    OC(O)R₁₁, OC(O)OR₁₁, N(R₁₄)C(O)N(R₁₄), OC(O)NR₁₄, N(R₁₄)C(O)OR₁₁,    halogen, OR₁₁, SR₁₁ or N(R₁₂)(R₁₃);    -   C₂–C₂₄alkyl which is interrupted once or more than once by        nonconsecutive O, S or NR₁₄ and which is unsubstituted or        substituted by phenyl, OR₁₁, SR₁₁, N(R₁₂)(R₁₃), CN, C(O)R₁₁,        C(O)OR₁₁, or C(O)N(R₁₄)₂;    -   C₂–C₂₄alkenyl which is uninterrupted or interrupted once or more        than once by nonconsecutive O, S or NR₁₄ and which is        unsubstituted or substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), or        C₁–C₁₂alkyl;    -   C₅–C₂₄cycloalkenyl which is uninterrupted or interrupted once or        more than once by nonconsecutive O, S or NR₁₄ and which is        unsubstituted or substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), or        C₁–C₁₂alkyl;    -   C₇–C₂₄arylalkyl which is unsubstituted or substituted on the        aryl group by C₁–C₁₂alkyl, C₁–C₁₂alkoxy or halogen;    -   C₄–C₂₄cycloalkyl which is uninterrupted or interrupted once or        more than once by O, S or NR₁₄ and which is unsubstituted or        substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), or C₁–C₁₂alkyl;    -   C₈–C₂₄arylcycloalkyl or C₈–C₂₄arylcycloalkenyl; or;-   R is a group of the formula

-    wherein    -   R₆, R₇, R₈, R₉ and R₁₀ independently of one another are        hydrogen, C₁–C₂₄alkyl;    -   C₂–C₂₄alkyl which is interrupted once or more than once by        nonconsecutive O, S or NR₁₄ and which is unsubstituted or        substituted by OH, SH; SR₁₁ or N(R₁₂)(R₁₃), OR₁₁, phenyl or        halogen;-   W is a bond, —CO—O— or —CO—N(R₁₅)—;-   L is a di-tri-or tetravalent linking group,-   n is a number of 2,3 or 4;-   R₁₁ is hydrogen, C₁–C₂₀alkyl, C₂–C₂₀alkenyl, C₃–C₈cycloalkyl, phenyl    unsubstituted or substituted by one or more C₁–C₄alkyl, benzyl or    C₂–C₂₀alkyl which is interrupted once or more than once by O or S    and which is unsubstituted or is substituted by OH or SH;-   R₁₂ and R₁₃ independently of one another are hydrogen, C₁–C₂₀alkyl,    C₃–C₈cycloalkyl, phenyl unsubstituted or substituted by one or more    C₁–C₄alkyl, benzyl or C₂–C₂₀alkyl which is interrupted once or more    than once by nonconsecutive O atoms and which is unsubstituted or    substituted by OH or SH; or R₁₂ and R₁₃ together are C₃–C₅alkylene    which is uninterrupted or interrupted by O, S or NR₁₄;-   R₁₄ is hydrogen, phenyl unsubstituted or substituted by one or more    C₁–C₄alkyl, C₁–C₁₂alkyl or C₂–C₁₂alkyl which is interrupted once or    more than once by nonconsecutive O or S atoms and which is    unsubstituted or substituted by OH or SH;-   R₁₅ is hydrogen, C₁–C₂₀alkyl, phenyl unsubstituted or substituted    once or more with C₁–C₄alkyl.    General Definitions

As used herein, the term “C₁–C₂₄alkyl” refers to straight and branchedaliphatic hydrocarbon chains, for example, C₁–C₂₄alkyl, C₁–C₂₀alkyl,C₁–C₁₈alkyl, C₁–C₁₂alkyl, C₁–C₈alkyl, C₁–C₆alkyl or C₁–C₄alkyl. Specificexamples are: methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl,tert-butyl, pentyl, isoamyl, n-hexyl, heptyl, 2,4,4-trimethylpentyl,2-ethylhexyl, octyl, nonyl, decyl, undecyl, dodecyl, tetradecyl,pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl ortetraicosyl. C₂–C₂₄alkyl which is interrupted once or more than once byO, S or NR₁₄ is, for example, interrupted 1–9 times, e.g. 1–7 times oronce or twice, by O, S or NR₁₄. It the radicals are interrupted by twoor more O, S or NR₁₄, then the O atoms, S atoms or NR₁₄ groups are ineach case separated from one another by at least one methylene group.The O atoms, S atoms or NR₁₄ groups are thus not directly consecutive.The alkyl radical can be linear or branched. For example, structuralunits such as —CH₂—O—CH₃, —CH₂CH₂—O—CH₂CH₃, —[CH₂CH₂O]_(z)—CH₃, wherez=1 to 9, —(CH₂CH₂O)₇CH₂CH₃, —CH₂—CH(CH₃)—O—CH₂—CH₂CH₃,—CH₂—CH(CH₃)—O—CH₂—CH₃, —CH₂SCH₃ or —CH₂—N(CH₃)₂ arise.

As used herein, the term “C₂–C₂₄Alkenyl” refers to radicals which aremono- or polyunsaturated, and are linear or branched and are, forexample, C₂–C₁₈alkenyl, C₂–C₈alkenyl, C₂–C₆alkenyl or C₂–C₄alkenyl.Examples are vinyl, allyl, methallyl, 1,1-dimethylallyl, 1-butenyl,2-butenyl, 1,3-pentadienyl, 1-hexenyl, 1-octenyl, decenyl or dodecenyl,in particular allyl. C₂–C₁₈Alkenyl has the same meanings as given aboveapart from the corresponding number of carbon atoms. If C₂–C₂₄alkenylradicals are interrupted, for example, by O, then the followingstructures are, for example, included: —(CH₂)_(y)—O—(CH₂)_(x)—CH═CH₂,—(CH₂)_(y)—O—(CH₂)_(x)—C(CH₃)═CH₂ or —(CH₂)_(y)O—CH═CH₂, where x and yindependently of one another are a number from 1 to 21.

As used herein, the term “C₁–C₂₄Alkylene” refers to linear or branchedand is, for example, C₁–C₂₀alkylene, C₁–C₁₂alkylene, C₁–C₈alkylene,C₂–C₈alkylene, C₁–C₄alkylene, for example methylene, ethylene,propylene, isopropylene, n-butylene, sec-butylene, isobutylene,tert-butylene, pentylene, hexylene, heptylene, octylene, nonylene,decylene, dodecylene, tetradecylene, heptadecylene, octadecylene,icosylene or e.g. C₁–C₁₂alkylene, for example ethylene, decylene,

C₂–C₁₈Alkylene is also linear or branched, e.g. C₂–C₈alkylene orC₂–C₄alkylene and has the meanings given above apart from thecorresponding number of carbon atoms. If C₂–C₂₄alkylene is interruptedonce or more than once by O, S or NR₁₄, then it is, for example,interrupted 1–9 times, e.g. 1–7 times or once or twice by O, S or NR₁₄,and, for example, structural units such as —CH₂—O—CH₂—,—CH₂CH₂—O—CH₂CH₂—, —[CH₂CH₂O]_(z)—, where z=1 to 9, —(CH₂CH₂O)₇CH₂CH₂—,—CH₂—CH(CH₃)—O—CH₂—CH(CH₃)—, —CH₂—S—CH₂—, —CH₂CH₂—S—CH₂CH₂—,—CH₂CH₂CH₂—S—CH₂CH₂CH₂—, —(CH₂)₃—S—(CH₂)₃—S—(CH₂)₃—, —CH₂—(NR₁₄)—CH₂— or—CH₂CH₂—(NR₁₄)—CH₂CH₂— arise. The alkylene radicals can be linear orbranched and, if the alkylene radicals are interrupted by two or more O,S or NR₁₄ groups, then the O, S and NR₁₄ are not consecutive, but ineach case are separated from one another by at least one methylenegroup.

As used herein, the term “C₂–C₂₄Alkenylene” refers to mono- orpolyunsaturated and linear or branched and e.g. C₂–C₁₈alkenylene orC₂–C₈alkenylene. Examples are ethenylene, propenylene, butenylene,pentenylene, hexenylene, octenylene, e.g. 1-propenylene, 1-butenylene,3-butenylene, 2-butenylene, 1,3-pentadienylene, 5hexenylene or7-octenylene. If C₂–C₂₄Alkenylene is interrupted once or more than onceby O, S, NR₁₄, then it is mono- or polyunsaturated and linear orbranched and is, for example, interrupted 1–9 times, e.g. 1–7 times oronce or twice, by O, S or NR₁₄, where in the case of two or more O, S orNR₁₄, these are in each case separated from one another by at least onemethylene group. Here, the meanings for C₂–C₂₄alkenylene are as definedabove.

As used herein, the term “C₃–C₂₄cycloalkyl, e.g. C₅–C₁₂cycloalkyl,C₃–C₁₂cycloalkyl, C₃–C₈cycloalkyl, stands both for individual alkyl ringsystems and also bridged alkyl ring systems. Furthermore, the radicalscan also contain linear or branched alkyl groups (as described aboveapart from the corresponding number of carbon atoms). Examples arecyclopropyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclododecyl,cycloicosyl, adamantyl, in particular cyclopentyl and cyclohexyl,preferably cyclohexyl.

Further examples are

C₃–C₈cycloalkyl, e.g. C₃–C₆cycloalkyl, can have the meaning given aboutapart form the corresponding number of carbon atoms.

C₃–C₁₈cycloalkyl substituted by C₁–C₂₀alkyl, OR₁₁, CF₃ or halogen ispreferably tri- or disubstituted in the 2,4,6- or 2,6-positionsrespectively, of the cycloalkyl ring. Preference is given to2,4,6-trimethylcyclohexyl and 2,6-dimethoxycyclohexyl. The cycloalkylgroup may be interrupted 1–9 times, e.g. 1–7 times or once or twice, byO, S or NR₁₄, where in the case of two or more O, S or NR₁₄, these arein each case separated from one another by at least one methylene group

As used herein, the term “C₃–C₂₄Cycloalkenyl”, e.g. C₅–C₁₂cycloalkenyl,C₃–C₁₂cycloalkenyl, C₃–C₈cycloalkenyl, stands both for individual alkylring systems and also bridged alkyl ring systems and can be mono- orpolyunsaturated, e.g. mono- or diunsaturated. Furthermore, the radicalscan also contain linear or branched alkyl groups (as described aboveapart from the corresponding number of carbon atoms). Examples arecyclopropenyl, cyclopentenyl, cyclohexenyl, cyclooctenyl,cyclododecenyl, cycloicosenyl, in particular cyclopentenyl andcyclohexenyl, preferably cyclohexenyl. The cycloalkenyl group may beinterrupted 1–9 times, e.g. 1–7 times or once or twice, by O, S or NR₁₄,where in the case of two or more O, S or NR₁₄, these are in each caseseparated from one another by at least one methylene group

As used herein, the term “C₄–C₁₈Cycloalkylene” is linear or branched andcan be either an individual ring or bridged alkyl rings, for exampleadamantyl. It is e.g. C₄–C₁₂cycloalkylene or C₄–C₈cycloalkylene, forexample cyclopentylene, cyclohexylene, cyclooctylene, cyclododecylene,in particular cyclopentylene and cyclohexylene, preferablycyclohexylene. However, C₄–C₁₈cycloalkylene likewise stands forstructural units such as

in which r and s independently of one another are 0–12 and the sum r+sis ≦12, or

in which r and s independently of one another are 0-13 and the sum r+sis —13. C₄–C₁₈cycloalkylene interrupted once or more than once by O, Sor NR₁₄ stands for cycloalkylene units as described above which can beinterrupted either in the ring unit or in the side-chain unit e.g. 1–9times, 1–7 times or once or twice, by O, S or NR₁₄.

As used herein, the term “C₃–C₂₄Cycloalkenylene” is linear or branchedand can be either an individual ring or bridged rings and is mono- orpolyunsaturated. It is e.g. C₃–C₁₂cycloalkenylene orC₃–C₈cycloalkenylene, for example cyclopentenylene, cyclohexenylene,cyclooctenylene, cyclododecenylene, in particular cyclopentenylene andcyclohexenylene, preferably cyclohexenylene. C₃–C₂₄Cycloalkenylene also,however, stands for structural units

such as

in which r and s independently of another are 0–12 and the sum r+s is≦12, or

or

in which r and s independently of one another are 0–13 and the sum r+sis ≦13. C₃–C₂₄Cycloalkenylene interrupted once or more than once by O, Sor NR₁₄ stands for cycloalkenylene units as described above which can beinterrupted either in the ring unit or in the side-chain unit e.g. 1–9times, 1–7 times or once or twice by O, S or NR₁₄. Examples are

Halogen is fluorine, chlorine, bromine or iodine, in particularfluorine, chlorine and bromine, preferably chlorine. R₁, R₁′, R₂, R₂′,R₃ and R₃′ as halogen are, in particular, chlorine.

As used herein, the term aryl is, for example, phenyl, naphthyl,biphenyl, anthracyl or phenanthryl.

As used herein, the term C₇–C₂₄Arylalkyl is, for example,C₇–C₁₆arylalkyl, C₇–C₁₁arylalkyl. The alkyl radical in this group caneither be linear or branched. Examples are benzyl, phenylethyl,α-methylbenzyl, phenylpentyl, phenylhexyl, α,α-dimethylbenzyl,naphthylmethyl, naphthylethyl, naphthyleth-1-yl ornaphthyl-1-methyl-eth-1-yl, in particular benzyl. SubstitutedC₇–C₂₄arylalkyl is substituted one to four times, e.g. once, twice orthree times, in particular once or twice, on the aryl ring.

As used herein, the term C₈–C₂₄Arylcycloalkyl is e.g.C₉–C₁₆arylcycloalkyl, C₉–C₁₃arylcycloalkyl and is cycloalkyl which isfused with one or more aryl rings. Examples are

Specific Definitions:Concerning the Residue A

The term “heterocyclic ring”, as used herein, refers to e.g. furyl,thienyl, pyrrolyl, oxinyl, dioxinyl or pyridyl. Said heterocyclicradicals can be mono- or polysubstituted, e.g. mono-substituted ordisubstituted, by halogen, linear or branched C₁–C₄alkyl, such asmethyl, ethyl, propyl, butyl, or C₁–C₄alkoxy. Examples thereof aredimethylpyridyl, dimethylpyrrolyl or methylluryl.

A is, for example, 2-methylnaphth-2-yl, 2-methoxynaphth-2-yl,1,3-dimethylnaphth-2-yl, 2,8-dimethylnaphth-1-yl,1,3-dimethoxynaphth-2-yl, 1,3-dichloronaphth-2-yl,2,8-dimethoxynaphth-1-yl, 2,4,6-trimethylpyrid-3-yl,2,4-dimethoxyfuran-3-yl or 2,4,5-trimethylthien-3-yl.

Preference is given to compounds of the formula I in which A is aradical

If case that two of the radicals R₁, R₂, R₃, R₄ or R₅ formC₂–C₁₂alkylene, then, for example, the following structures arise

The alkylene chain may be interrupted by —O—, —S— or —NR₁₄.

Preferred are compounds of the formula I in which

-   A is a group

-    wherein-   R₁ and R₂ independently of one another are C₁–C₁₂alkyl, OR₁₁, CF₃ or    halogen; more preferably C₁–C₄alkyl, C₁–C₄alkoxy, CF₃ or Cl;-   R₃, R₄ and R₅ independently of one another are hydrogen,    C₁–C₁₂alkyl, OR₁₁ or halogen; more preferably hydrogen, C₁–C₄alkyl,    C₁–C₄alkoxy or Cl.

The residue R, may be an aliphatic or an aromatic residue.

The aliphatic residue R is preferably

-   -   C₁–C₁₂alkyl, unsubstituted or substituted by phenyl, CN, OR₁₁,        C(O)R₁₁, C(O)OR₁₁, C(O)N(R₁₄)₂;    -   C₂–C₁₂alkyl which is interrupted once or more than once by        nonconsecutive O and which is unsubstituted or substituted by        phenyl, CN, OR₁₁, C(O)R₁₁, C(O)OR₁₁, C(O)N(R₁₄)₂;    -   C₂–C₁₂alkenyl which is uninterrupted or interrupted once or more        than once by nonconsecutive O and which is unsubstituted or        substituted by OR₁₁, N(R₁₂)(R₁₃), or C₁–C₁₂alkyl;    -   benzyl;    -   C₄–C₈cycloalkyl which is uninterrupted or interrupted once or        more than once by O, S or NR₁₄ and which is unsubstituted or        substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), or C₁–C₁₂alkyl;    -   C₈–C₁₂arylcycloalkyl; whereby

-   R₁₁ is hydrogen, C₁–C₁₂alkyl, C₅–C₆cycloalkyl, phenyl or benzyl;

-   R₁₂ and R₁₃ independently of one another are hydrogen, C₁–C₁₂alkyl,    phenyl, benzyl or C₂–C₁₂alkyl which is interrupted once or more than    once by nonconsecutive O atoms and which is unsubstituted or    substituted by OH or SH; or R₁₂ and R₁₃ together are piperidino,    morpholino or piperazino;;

-   R₁₄ is hydrogen, phenyl, C₁–C₁₂alkyl or C₂–C₁₂alkyl which is    interrupted once or more than once by nonconsecutive O atoms and    which is unsubstituted or substituted by OH or SH;

Most preferably the aliphatic residue R is C₁–C₁₂alkyl.

The aromatic residue R is preferably a group of the formula

-   -   wherein    -   R₆, R₇, R₈, R₉ and R₁₀ independently of one another are        hydrogen, C₁–C₁₂alkyl, OR₁₁, phenyl or halogen; more preferably        C₁–C₄alkyl; C₁–C₄alkoxy, phenyl or Cl.

The divalent linking group is selected from arylene, linear or branchedC₂–C₂₄alkylene which is unsubstituted or substituted once or more thanonce by C₁–C₂₀alkyl, C₁–C₂₀alkoxy, —S—C₁–C₂₀alkyl, phenoxy, —O-aryl,—O—CO-aryl, O—CO—C₁–C₂₀alkyl, —N—(CO—C₁–C₂₀alkyl)₂,—CO—N—(C₁–C₂₀alkyl)₂, —COO—C₁–C₂₀alkyl, —COO-aryl, CN, CF₃, F, CH₂Cl,CH₂Br, linear or branched C₂–C₂₄alkylene which is interrupted once ormore than once by non-consecutive —O—, —S— atoms or by groups selectedfrom —N(R₁₆)—, —CO—N(R₁₆)—, —CO—, —O—CO—, —CO—O—, —O—COO—, phenylene,arylene, cycloalkylene, —CH═CH—, bicycloalkylene, biphenylene,—Si(CH₃)₂—, —Si(CH₃)₂—O—Si(CH₃)₂—, —Si(CH₃)₂—O-phenylene-O—Si(CH₃)₂—,—CF₂— or 2,2-dimethyl-1,3-dioxolane-4,5-diyl, and which is unsubstitutedor substituted once or more than once by C₁–C₂₀alkyl, C₁–C₂₀alkoxy,—S—C₁–C₂₀alkyl, phenoxy, —O-aryl, —O—CO-aryl, O—CO—C₁–C₂₀alkyl,—N—(CO—C₁–C₂₀alkyl)₂, —CO—N—(C₁–C₂₀alkyl)2, —COO—C₁–C₂₀alkyl, —COO-aryl,CN, CF₃, F, CH₂Cl, CH₂Br; with the proviso, that L is not ethylene.

The group R₁₀ is C₁–C₂₀alkyl, —CO—C₁–C₂₀alkyl, aryl, —CO-aryl.

The trivalent linking group is selected from linear or branchedC₃–C₂₄alkylene which is unsubstituted or substituted once or more thanonce by C₁–C₂₀alkyl, C₁–C₂₀alkoxy, —S—C₁–C₂₀alkyl, phenoxy, —O-aryl,—O—CO-aryl, O—CO—C₁–C₂₀alkyl, —N—(CO—C₁–C₂₀alkyl)₂,—CO—N—(C₁–C₂₀alkyl)₂, —COO—C₁–C₂₀alkyl, —COO-aryl, CN, CF₃, F, CH₂Cl,CH₂Br, linear or branched C₃–C₂₄alkylene which is interrupted once ormore than once by non-consecutive —O—, —S— atoms or by groups selectedfrom —N(R₁₈)—, —CO—N(R₁₆)—, —CO—, —O—CO—, —CO—O—, —O—COO—, phenylene,arylene, cycloalkylene, —CH═CH—, bicycloalkylene, biphenylene,—Si(CH₃)₂—, —Si(CH₃)₂—O—Si(CH₃)₂—, —Si(CH₃)₂—O-phenylene-O—Si(CH₃)₂—,—CF₂— or 2,2-dimethyl-1,3-dioxolane-4,5-diyl, and which is unsubstitutedor substituted once or more than once by C_(-C) ₂₀alkyl, C₁–C₂₀alkoxy,—S—C₁–C₂₀alkyl, phenoxy, —O-aryl, —O—CO-aryl, O—CO—C₁–C₂₀alkyl,—N—(CO—C₁–C₂₀alkyl)₂, —CO—N—(CO—C₁–C₂₀alkyl)2, —COO—C₁–C₂₀alkyl,—COO-aryl, CN, CF₃, F, CH₂Cl, CH₂Br, or the trivalent linking group isselected from —[—(C₁–C₂₄alkyl)-O—]₃—P or —[—(C₁–C₂₄alkyl)-O—]₃—P═O or isa group of the formula

The tetravalent linking group is selected from linear or branchedC₄–C₂₄alkylene which is unsubstituted or substituted once or more thanonce by C₁–C₂₀alkyl, C₁–C₂₀alkoxy, —S—C₁–C₂₀alkyl, phenoxy, —O-aryl,—O—CO-aryl, O—CO—C₁–C₂₀alkyl, —N—(CO—C₁–C₂₀alkyl)₂,—CO—N—(C₁–C₂₀alkyl)2, —COO—C₁–C₂₀alkyl, —COO-aryl, CN, CF₃, F, CH₂Cl,CH₂Br, linear or branched C₄–C₂₄alkylene which is interrupted once ormore than once by non-consecutive —O—, —S— atoms or by groups selectedfrom —N(R₁₆)—, —CO—N(R₁₆)—, —CO—, —O—CO—, —CO—O—, —O—COO—, phenylene,arylene, cycloalkylene, —CH═CH—, bicycloalkylene, biphenylene,—Si(CH₃)₂—, —Si(CH₃)₂—O—Si(CH₃)₂—, —Si(CH₃)₂—O-phenylene-O—Si(CH₃)₂—,—CF₂— or 2,2-dimethyl-1,3-dioxolane-4,5-diyl, and which is unsubstitutedor substituted once or more than once by C₁–C₂₀alkyl, C₁–C₂₀alkoxy,—S—C₁–C₂₀alkyl, phenoxy, —O-aryl, —O—CO-aryl, O—CO—C₁–C₂₀alkyl,—N—(CO—C₁–C₂₀alkyl)₂, —CO—N—(C₁–C₂₀alkyl)2, —COO—C₁–C₂₀alkyl, —COO-aryl,CN, CF₃, F, CH₂Cl, CH₂Br; or the tetravalent linking group is a group ofthe formula

The term arylene used to define the divalent linking group refers to thefollowing groups:

The above arylene groups may also contain more than 2 free bonds and arethus suitable as tri-or tetravalent linkers as well.

Concerning the linking groups, the term aryl as used in the groupsO-aryl, —O—CO-aryl, —COO-aryl refers for example, to phenyl, naphthyl,biphenyl, anthracyl or phenanthryl.

When W has the meaning of —COO— or —CO—N(R₁₅)—, the di-tri-ortetravalent linking group can also refer to structures like for example,

with X═—CH₂—, —CF₂—, —CH(CH₃)—, —C(CH₃)₃—, —C(CF₃)₃—, O, S, CO, SO, SO₂.

Preferably the linking group is a divalent linking group.

Depending on the group W, the following molecules are obtained:

Preferred Compounds:

Of particular interest are compounds of the formula I

in which

-   E is O or S and x is 0 or 1;-   A is a group

-    wherein    -   R₁ and R₂ independently of one another are C₁–C₁₂alkyl, OR₁₁,        CF₃ or halogen;    -   R₃, R₄ and R₅ independently of one another are hydrogen,        C₁–C₁₂alkyl, OR₁₁ or halogen;-   R is C₁–C₁₂alkyl, unsubstituted or substituted by phenyl, CN, OR₁₁,    C(O)R₁₁, C(O)OR₁₁, C(O)N(R₁₄)₂;    -   C₂–C₁₂alkyl which is interrupted once or more than once by        nonconsecutive O and which is unsubstituted or substituted by        phenyl, CN, OR₁₁, C(O)R₁₁, C(O)OR₁₁, C(O)N(R₁₄)₂;    -   C₂–C₁₂alkenyl which is uninterrupted or interrupted once or more        than once by nonconsecutive O and which is unsubstituted or        substituted by OR₁₁, N(R₁₂)(R₁₃), or C₁–C₁₂alkyl;    -   benzyl;    -   C₄–C₈cycloalkyl which is uninterrupted or interrupted once or        more than once by O, S or NR₁₄ and which is unsubstituted or        substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), or C₁–C₁₂alkyl;    -   C₈–C₁₂arylcycloalkyl; or;-   R is a group of the formula

-   -   wherein    -   R₆, R₇, R₈, R₉ and R₁₀ independently of one another are        hydrogen, C₁–C₁₂alkyl;    -   OR₁₁, phenyl or halogen;

-   W is a bond, —CO—O— or —CO—N(R₁₅)—;

-   L is a di- or trivalent linking group,

-   n is a number of 2 or 3;

-   R₁₁ is hydrogen, C₁–C₁₂alkyl, C₅–C₆cycloalkyl, phenyl or benzyl;

-   R₁₂ and R₁₃ independently of one another are hydrogen, C₁–C₁₂alkyl,    phenyl, benzyl or C₂–C₁₂alkyl which is interrupted once or more than    once by nonconsecutive O atoms and which is unsubstituted or    substituted by OH or SH; or R₁₂ and R₁₃ together are piperidino,    morpholino or piperazino;;

-   R₁₄ is hydrogen, phenyl, C₁–C₁₂alkyl or C₂–C₁₂alkyl which is    interrupted once or more than once by nonconsecutive O atoms and    which is unsubstituted or substituted by OH or SH;

-   R₁₅ is hydrogen, C₁–C₁₂alkyl, phenyl unsubstituted or substituted    once or more with C₁–C₄alkyl.

Especially preferred are compounds of the formula I

in which

-   E is O and x is 1;-   A is a group

-    wherein    -   R₁ and R₂ independently of one another are C₁–C₄alkyl,        C₁–C₄alkoxy, CF₃ or Cl;    -   R₃, R₄ and R₅ independently of one another are hydrogen,        C₁–C₄alkyl, C₁–C₄alkoxy or Cl;-   R is C₁–C₁₂alkyl, or;-   R is a group of the formula

-   -   wherein    -   R₆, R₇, R₈, R₉ and R₁₀ independently of one another are        hydrogen, C₁–C₄alkyl, C₁–C₄alkoxy, phenyl or Cl;

-   W is a bond;

-   L is a di-valent linking group,

-   n is a number of 2.

The compounds may be prepared starting from a compound of the formula II

wherein A and R are as described above and M is hydrogen, Li, Na, K,preferably Li.

Compounds of the formula II, wherein R═Ra and

-   Ra is C₁–C₂₄alkyl, unsubstituted or substituted by C₃–C₂₄cycloalkyl,    C₃–C₂₄cycloalkenyl, phenyl, CN, C(O)R₁₁, C(O)OR₁₁, C(O)N(R₁₄)₂,    OC(O)R₁₁, OC(O)OR₁₁, N(R₁₄)C(O)N(R₁₄), OC(O)NR₁₄, N(R₁₄)C(O)OR₁₁,    halogen, OR₁₁, SR₁₁ or N(R₁₂)(R₁₃);    -   C₂–C₂₄alkyl which is interrupted once or more than once by        nonconsecutive O, S or NR₁₄ and which is unsubstituted or        substituted by phenyl, OR₁₁, SR₁₁, N(R₁₂)(R₁₃), CN, C(O)R₁₁,        C(O)OR₁₁, or C(O)N(R₁₄)₂;    -   C₂–C₂₄alkenyl which is uninterrupted or interrupted once or more        than once by nonconsecutive O, S or NR₁₄ and which is        unsubstituted or substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), or        C₁–C₁₂alkyl;    -   C₅–C₂₄cycloalkenyl which is uninterrupted or interrupted once or        more than once by nonconsecutive O, S or NR₁₄ and which is        unsubstituted or substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), or        C₁–C₁₂alkyl;    -   C₇–C₂₄arylalkyl which is unsubstituted or substituted on the        aryl group by C₁–C₁₂alkyl, C₁–C₁₂alkoxy or halogen;    -   C₄–C₂₄cycloalkyl which is uninterrupted or interrupted once or        more than once by O, S or NR₁₄ and which is unsubstituted or        substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), or C₁–C₁₂alkyl;    -   C₈–C₂₄arylcycloalkyl or C₈–C₂₄arylcycloalkenyl;        are described in the British Patent Application 0112580.6 filed        May, 24, 2001

Examples of compounds of the formula II as described in the BritishPatent Application 0112580.6 are: lithium(2,6-dimethylbenzoyl)ethylphosphine, lithium(2,6-diethylbenzoyl)ethylphosphine, lithium(2,4,6-trimethylbenzoyl)ethylphosphine, lithium(2,3,4,5,6-pentamethylbenzoyl)ethylphosphine, lithium(2,3,5,6-tetramethylbenzoyl)ethylphosphine, lithium(2,4,6-triisopropylbenzoyl)ethylphosphine, lithium(2,4,5,6-tetramethylbenzoyl)ethylphosphine, lithium(2,4,6-tri-tert-butylbenzoyl)ethylphosphine, lithium(2,6-dimethyl-4-tert-butylbenzoyl)ethylphosphine, lithium(2,6-diphenoxymethylbenzoyl)ethylphosphine, lithium(2,3,6-trimethylbenzoyl)ethylphosphine, lithium(2,3,4,6-tetramethylbenzoyl)ethylphosphine, lithium(2-phenyl-6-methylbenzoyl)ethylphosphine, lithium(2,4,6-trimethoxybenzoyl)ethylphosphine, lithium(2,4-dimethoxybenzoyl)ethylphosphine, lithium(2,3,6-trimethoxybenzoyl)ethylphosphine, lithium(2,6-diethoxybenzoyl)ethylphosphine, lithium(2,6-dimethoxy-3,5-dimethylbenzoyl)ethylphosphine, lithium(2,6-dimethoxy-4-methylbenzoyl)ethylphosphine, lithium(2,6-dimethoxy-3-bromobenzoyl)ethylphosphine, lithium(2,6-dimethoxy-3-chlorobenzoyl)ethylphosphine, lithium(2,6-dimethoxy-3-chloro-5-bromobenzoyl)ethylphosphine, lithium(2,6-dimethoxy-3,5-di-chlorobenzoyl)ethylphosphine, lithium(2,3,6-trimethoxy-5-bromobenzoyl)ethylphosphine, lithium(2,6-dichlorobenzoyl)ethylphosphine, lithium(2,4,6-trichlorobenzoyl)ethylphosphine, lithium(2,3,6-trichlorobenzoyl)ethylphosphine, lithium(2,3,5,6-tetrachlorobenzoyl)ethylphosphine, lithium(2,3,4,5,6-pentachlorobenzoyl)ethylphosphine, lithium(2,6-dichloro-3-methylbenzoyl)ethylphosphine, lithium(2-chloro-6-methylbenzoyl)ethylphosphine, lithium(2-methoxy-3,6-dichlorobenzoyl)ethylphosphine, lithium(2-methoxy-6-chlorobenzoyl)ethylphosphine, lithium(2,6-bis(trifluoromethyl)benzoyl)ethylphosphine, lithium(2-chloro-6-methylthiobenzoyl)ethylphosphine, lithium(2,6-dibromobenzoyl)ethylphosphine, lithium(2,6-dimethylbenzoyl)-n-butylphosphine, lithium(2,6-diethylbenzoyl)-n-butylphosphine, lithium(2,4,6-tri-methylbenzoyl)-n-butylphosphine, lithium(2,3,4,5,6-pentamethylbenzoyl)-n-butylphosphine, lithium(2,3,5,6-tetramethylbenzoyl)-n-butylphosphine, lithium(2,4,6-triisopropylbenzoyl)-n-butylphosphine, lithium(2,4,5,6-tetramethylbenzoyl)-n-butylphosphine, lithium(2,4,6-tri-tert-butylbenzoyl)-n-butylphosphine, lithium(2,6-dimethyl-4-tert-butylbenzoyl)-n-butylphosphine, lithium(2,6-diphenoxymethylbenzoyl)-n-butylphosphine, lithium(2,3,6-trimethylbenzoyl)-n-butylphosphine, lithium(2,3,4,6-tetramethylbenzoyl)-n-butylphosphine, lithium(2-phenyl-6-methylbenzoyl)-n-butylphosphine, lithium(2,4,6-trimethoxybenzoyl)-n-butylphosphine, lithium(2,4-dimethoxybenzoyl)-n-butylphosphine, lithium(2,3,6-trimethoxybenzoyl)-n-butylphosphine, lithium(2,6-diethoxybenzoyl)-n-butylphosphine, lithium(2,6-dimethoxy-3,5-dimethylbenzoyl)-n-butylphosphine, lithium(2,6-dimethoxy-4-methylbenzoyl)-n-butylphosphine, lithium(2,6-dimethoxy-3-bromobenzoyl)-n-butylphosphine, lithium(2,6-dimethoxy-3-chlorobenzoyl)-n-butylphosphine, lithium(2,6-dimethoxy-3-chloro-5-bromobenzoyl)-n-butylphosphine, lithium(2,6-dimethoxy-3,5-dichlorobenzoyl)-n-butylphosphine, lithium(2,3,6-trimethoxy-5-bromobenzoyl)-n-butylphosphine, lithium(2,6-dichlorobenzoyl)-n-butylphosphine, lithium(2,4,6-trichlorobenzoyl)-n-butylphosphine, lithium(2,3,6-trichlorobenzoyl)-n-butylphosphine, lithium(2,3,5,6-tetrachlorobenzoyl)-n-butylphosphine, lithium(2,3,4,5,6-penta-chlorobenzoyl)-n-butylphosphine, lithium(2,6-dichloro-3-methylbenzoyl)-n-butylphosphine, lithium(2-chloro-6-methylbenzoyl)-n-butylphosphine, lithium(2-methoxy-3,6-dichlorobenzoyl)-n-butylphosphine, lithium(2-methoxy-6-chlorobenzoyl)-n-butylphosphine, lithium(2,6-bis(trifluoromethyl)benzoyl)-n-butylphosphine, lithium(2-chloro-6-methylthiobenzoyl)-n-butylphosphine, lithium(2,6-dibromobenzoyl)-n-butylphosphine, lithium(2,6-dimethylbenzoyl)isobutylphosphine, lithium(2,6-diethylbenzoyl)isobutylphosphine, lithium(2,4,6-trimethylbenzoyl)isobutylphosphine, lithium(2,3,4,5,6-pentamethylbenzoyl)isobutylphosphine, lithium(2,3,5,6-tetramethylbenzoyl)isobutylphosphine, lithium(2,4,6-triisopropylbenzoyl)isobutylphosphine, lithium(2,4,5,6-tetramethylbenzoyl)isobutylphosphine, lithium(2,4,6-tri-tert-butylbenzoyl)isobutylphosphine, lithium(2,6-dimethyl-4-tert-butylbenzoyl)isobutylphosphine, lithium(2,6-diphenoxymethylbenzoyl)isobutylphosphine, lithium(2,3,6-trimethylbenzoyl)isobutylphosphine, lithium(2,3,4,6-tetramethylbenzoyl)isobutylphosphine, lithium(2-phenyl-6-methylbenzoyl)isobutylphosphine, lithium(2,4,6-trimethoxybenzoyl)isobutylphosphine, lithium(2,4-dimethoxybenzoyl)isobutylphosphine, lithium(2,3,6-trimethoxybenzoyl)isobutylphosphine, lithium(2,6-diethoxybenzoyl)isobutylphosphine, lithium(2,6-dimethoxy-3,5-dimethylbenzoyl)isobutylphosphine, lithium(2,6-dimethoxy-4-methylbenzoyl)isobutylphosphine, lithium(2,6-dimethoxy-3-bromobenzoyl)isobutylphosphine, lithium(2,6-dimethoxy-3-chlorobenzoyl)isobutylphosphine, lithium(2,6-dimethoxy-3-chloro-5-bromobenzoyl)isobutylphosphine, lithium(2,6-dimethoxy-3,5-dichlorobenzoyl)isobutylphosphine, lithium(2,3,6-trimethoxy-5-bromobenzoyl)isobutylphosphine, lithium(2,6-dichlorobenzoyl)isobutylphosphine, lithium(2,4,6-trichlorobenzoyl)isobutylphosphine, lithium(2,3,6-trichlorobenzoyl)isobutylphosphine, lithium(2,3,5,6-tetrachlorobenzoyl)isobutylphosphine, lithium(2,3,4,5,6-pentachlorobenzoyl)isobutylphosphine, lithium(2,6-dichloro-3-methylbenzoyl)isobutylphosphine, lithium(2-chloro-6-methylbenzoyl)isobutylphosphine, lithium(2-methoxy-3,6-dichlorobenzoyl)isobutylphosphine, lithium(2-methoxy-6-chlorobenzoyl)isobutylphosphine, lithium(2,6-bis(trifluoromethyl)-benzoyl)isobutylphosphine, lithium(2-chloro-6-methylthiobenzoyl)isobutylphosphine, lithium(2,6-dibromobenzoyl)isobutylphosphine, lithium(2,6-dimethylbenzoyl)-1-methylpropylphosphine, lithium(2,6-diethylbenzoyl)-1-methylpropylphosphine, lithium(2,4,6-trimethylbenzoyl)-1-methylpropylphosphine, lithium(2,3,4,5,6-pentamethylbenzoyl)-1-methylpropylphosphine, lithium(2,3,5,6-tetramethylbenzoyl)-1-methylpropylphosphine, lithium(2,4,6-triisopropylbenzoyl)-1-methylpropylphosphine, lithium(2,4,5,6-tetramethylbenzoyl)-1-methylpropylphosphine, lithium(2,4,6-tri-tert-butylbenzoyl)-1-methylpropylphosphine, lithium(2,6-dimethyl-4tert-butylbenzoyl)-1-methylpropylphosphine, lithium(2,6-diphenoxymethylbenzoyl)-1-methylpropylphosphine, lithium(2,3,6-trimethylbenzoyl)-1-methylpropylphosphine, lithium(2,3,4,6-tetramethylbenzoyl)-1-methylpropylphosphine, lithium(2-phenyl-6-methylbenzoyl)-1-methylpropylphosphine, lithium(2,4,6-trimethoxybenzoyl)-1-methylpropylphosphine, lithium(2,4-dimethoxybenzoyl)-1-methylpropylphosphine, lithium(2,3,6-trimethoxybenzoyl)-1-methylpropylphosphine, lithium(2,6-diethoxybenzoyl)-1-methylpropylphosphine, lithium(2,6-dimethoxy-3,5-dimethylbenzoyl)-1-methylpropylphosphine, lithium(2,6-dimethoxy-4-methylbenzoyl)-1-methylpropylphosphine, lithium(2,6-dimethoxy-3-bromobenzoyl)-1-methylpropylphosphine, lithium(2,6-dimethoxy-3-chlorobenzoyl)-1-methylpropylphosphine, lithium(2,6-dimethoxy-3-chloro-5-bromobenzoyl)-1-methylpropylphosphine, lithium(2,6-dimethoxy-3,5-dichlorobenzoyl)-1-methylpropylphosphine, lithium(2,3,6-trimethoxy-5-bromobenzoyl)-1-methylpropylphosphine, lithium(2,6-dichlorobenzoyl)-1-methylpropylphosphine, lithium(2,4,6-trichlorobenzoyl)-1-methylpropylphosphine, lithium(2,3,6-trichlorobenzoyl)-1-methylpropylphosphine, lithium(2,3,5,6-tetrachlorobenzoyl)-1-methylpropylphosphine, lithium(2,3,4,5,6-pentachlorobenzoyl)-1-methylpropylphosphine, lithium(2,6-dichloro-3-methylbenzoyl)-1-methylpropylphosphine, lithium(2-chloro-6-methylbenzoyl)-1-methylpropylphosphine, lithium(2-methoxy-3,6-dichlorobenzoyl)-1-methylpropylphosphine, lithium(2-methoxy-6-chlorobenzoyl)-1-methylpropylphosphine, lithium(2,6-bis-(trifluoromethyl)benzoyl)-1-methylpropylphosphine, lithium(2-chloro-6-methylthiobenzoyl)-1-methylpropylphosphine, lithium(2,6-dibromobenzoyl)-1-methylpropylphosphine, lithium(2,6-dimethylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,6-diethylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,4,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,3,4,5,6-pentamethylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,3,5,6-tetramethylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,4,6-triisopropylbenzoyl)-2,4,4-tri-methylpentylphosphine, lithium(2,4,5,6-tetramethylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,4,6-tri-tert-butylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,6-dimethyl-4-tert-butylbenzoyl)-2,4,4-trimethylpentylphosphine,lithium (2,6-diphenoxymethylbenzoyl)-2,4,4-trimethylpentylphosphine,lithium (2,3,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,3,4,6-tetramethylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2-phenyl-6-methylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,4,6-trimethoxybenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,4-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,3,6-trimethoxybenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,6-diethoxybenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,6-dimethoxy-3,5-dimethylbenzoyl)-2,4,4-trimethylpentylphosphine,lithium (2,6-dimethoxy-4-methylbenzoyl)-2,4,4-trimethylpentylphosphine,lithium (2,6-dimethoxy-3-bromobenzoyl)-2,4,4-trimethylpentylphosphine,lithium (2,6-dimethoxy-3-chlorobenzoyl)-2,4,4-trimethylpentylphosphine,lithium(2,6-dimethoxy-3-chloro-5-bromobenzoyl)-2,4,4-trimethylpentylphosphine,lithium(2,6-dimethoxy-3,5-dichlorobenzoyl)-2,4,4-trimethylpentylphosphine,lithium(2,3,6-trimethoxy-5-bromobenzoyl)-2,4,4-trimethylpentylphosphine,lithium (2,6-dichlorobenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,4,6-trichlorobenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,3,6-trichlorobenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,3,5,6-tetrachlorobenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,3,4,5,6-pentachlorobenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,6-dichloro-3-methylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2-chloro-6-methylbenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2-methoxy-3,6-dichlorobenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2-methoxy-6-chlorobenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,6-bis(trifluoromethyl)benzoyl)-2,4,4-trimethylpentylphosphine,lithium (2-chloro-6-methylthiobenzoyl)-2,4,4-trimethylpentylphosphine,lithium (2,6-dibromobenzoyl)-2,4,4-trimethylpentylphosphine, lithium(2,6-dimethylbenzoyl)cyclopentylphosphine, lithium(2,6-diethylbenzoyl)cyclopentylphosphine, lithium(2,4,6-trimethylbenzoyl)cyclopentylphosphine, lithium(2,3,4,5,6-pentamethylbenzoyl)cyclopentylphosphine, lithium(2,3,5,6-tetramethylbenzoyl)cyclopentylphosphine, lithium(2,4,6-triisopropylbenzoyl)cyclopentylphosphine, lithium(2,4,5,6-tetramethylbenzoyl)cyclopentylphosphine, lithium(2,4,6-tri-tert-butylbenzoyl)cyclopentylphosphine, lithium(2,6-dimethyl-4-tert-butylbenzoyl)cyclopentylphosphine, lithium(2,6-diphenoxymethylbenzoyl)cyclopentylphosphine, lithium(2,3,6-trimethylbenzoyl)cyclopentylphosphine, lithium(2,3,4,6-tetramethylbenzoyl)cyclopentylphosphine, lithium(2-phenyl-6-methylbenzoyl)cyclopentylphosphine, lithium(2,4,6-trimethoxybenzoyl)cyclopentylphosphine, lithium(2,4-dimethoxybenzoyl)cyclopentylphosphine, lithium(2,3,6-trimethoxybenzoyl)cyclopentylphosphine, lithium(2,6-diethoxybenzoyl)cyclopentylphosphine, lithium(2,6-dimethoxy-3,5-dimethylbenzoyl)cyclopentylphosphine, lithium(2,6-dimethoxy-4-methylbenzoyl)cyclopentylphosphine, lithium(2,6-dimethoxy-3-bromobenzoyl)cyclopentylphosphine, lithium(2,6-dimethoxy-3-chlorobenzoyl)cyclopentylphosphine, lithium(2,6-dimethoxy-3-chloro-5-bromobenzoyl)cyclopentylphosphine, lithium(2,6-dimethoxy-3,5-dichlorobenzoyl)cyclopentylphosphine, lithium(2,3,6-trimethoxy-5-bromobenzoyl)cyclopentylphosphine, lithium(2,6-dichlorobenzoyl)cyclopentylphosphine, lithium(2,4,6-trichlorobenzoyl)cyclopentylphosphine, lithium(2,3,6-trichlorobenzoyl)cyclopentylphosphine, lithium(2,3,5,6-tetrachlorobenzoyl)cyclopentylphosphine, lithium(2,3,4,5,6-pentachlorobenzoyl)cyclopentylphosphine, lithium(2,6-dichloro-3-methylbenzoyl)cyclopentylphosphine, lithium(2-chloro-6-methylbenzoyl)cyclopentylphosphine, lithium(2-methoxy-3,6-dichlorobenzoyl)cyclopentylphosphine, lithium(2-methoxy-6-chlorobenzoyl)-cyclopentylphosphine, lithium(2,6-bis(trifluoromethyl)benzoyl)cyclopentylphosphine, lithium(2-chloro-6-methylthiobenzoyl)cyclopentylphosphine, lithium(2,6-dibromobenzoyl)cyclopentylphosphine, lithium(2,6-dimethylbenzoyl)cyclohexylphosphine, lithium(2,6-diethylbenzoyl)cyclohexylphosphine, lithium(2,4,6-trimethylbenzoyl)cyclohexylphosphine, lithium(2,3,4,5,6-pentamethylbenzoyl)cyclohexylphosphine, lithium(2,3,5,6-tetramethylbenzoyl)cyclohexylphosphine, lithium(2,4,6-triisopropylbenzoyl)cyclohexylphosphine, lithium(2,4,5,6-tetramethylbenzoyl)cyclohexylphosphine, lithium(2,4,6-tri-tert-butylbenzoyl)cyclohexylphosphine, lithium(2,6-dimethyl-4-tert-butylbenzoyl)cyclohexylphosphine, lithium(2,6-diphenoxymethylbenzoyl)cyclohexylphosphine, lithium(2,3,6-trimethylbenzoyl)cyclohexylphosphine, lithium(2,3,4,6-tetramethylbenzoyl)cyclohexylphosphine, lithium(2-phenyl-6-methylbenzoyl)cyclohexylphosphine, lithium(2,4,6-trimethoxybenzoyl)cyclohexylphosphine, lithium(2,4-dimethoxybenzoyl)cyclohexylphosphine, lithium(2,3,6-trimethoxybenzoyl)cyclohexylphosphine, lithium(2,6-diethoxybenzoyl)cyclohexylphosphine, lithium(2,6-dimethoxy-3,5-dimethylbenzoyl)cyclohexylphosphine, lithium(2,6-dimethoxy-4-methylbenzoyl)cyclohexylphosphine, lithium(2,6-dimethoxy-3-bromobenzoyl)cyclohexylphosphine, lithium(2,6-dimethoxy-3-chlorobenzoyl)cyclohexylphosphine, lithium(2,6-dimethoxy-3-chloro-5-bromobenzoyl)cyclohexylphosphine, lithium(2,6-dimethoxy-3,5-dichlorobenzoyl)cyclohexylphosphine, lithium(2,3,6-trimethoxy-5-bromobenzoyl)cyclohexylphosphine, lithium(2,6-dichlorobenzoyl)cyclohexylphosphine, lithium(2,4,6-trichlorobenzoyl)cyclohexylphosphine, lithium(2,3,6-trichlorobenzoyl)cyclohexylphosphine, lithium(2,3,5,6-tetrachlorobenzoyl)cyclohexylphosphine, lithium(2,3,4,5,6-pentachlorobenzoyl)cyclohexylphosphine, lithium(2,6-dichloro-3-methylbenzoyl)cyclohexylphosphine, lithium(2-chloro-6-methylbenzoyl)cyclohexylphosphine, lithium(2-methoxy-3,6-dichlorobenzoyl)cyclohexylphosphine, lithium(2-methoxy-6-chlorobenzoyl)cyclohexylphosphine, lithium(2,6-bis(trifluoromethyl)benzoyl)cyclohexylphosphine, lithium(2-chloro-6-methylthiobenzoyl)cyclohexylphosphine, lithium(2,6-dibromobenzoyl)cyclohexylphosphine.

The preparation of the compounds of formula II as described in theBritish Patent Application 0112580.6 can be summarized as follows:

-   (1) Reaction of an acyl halide of the formula IV

-    in which-   A is as defined above and X is Cl or Br;    with a dimetalated organophosphine of the formula V

in which

-   R_(a) is as defined above and M₁ is Na, Li or K in the molar ratio    1:1; and-   (2) where appropriate, subsequent hydrolysis if compounds of the    formula II in which M is hydrogen are to be obtained.

The starting materials are advantageously reacted in the molar ratio1:1. A slight excess of one or the other of the components, e.g. up to20%, is not critical. In this case the desired product is formed too,although the proportion of undesired byproducts may be influenced.

The reaction is advantageously carried out in a solvent. In particular,as solvents, it is possible to use ethers which are liquid atatmospheric pressure and room temperature. Examples are dimethyl ether,diethyl ether, methyl propyl ether, 1,2-dimethoxyethane,bis(2-methoxyethyl)ether, dioxane or tetrahydrofuran. Preference isgiven to using tetrahydrofuran.

The reaction temperatures are advantageously −60° C. to +120° C., e.g.−40° C. to 100° C., for example −20° C. to +80° C.

It is advisable to stir the reaction mixture.

It is advantageous to initially introduce the compound of the formula Vand to add dropwise the compound of the formula IV at the temperaturesgiven above. Here, the compound of the formula IV can be added without adiluent or else diluted with the reaction solvent. If desired, thecourse of the reaction can be monitored using methods customary in theart, for example NMR, for example ³¹P-NMR, chromatography (thin-layer,HPLC, GC) etc. In the reactions described above, it is essential to workin an inert gas atmosphere, e.g. with a protective gas such as argon ornitrogen, in order to exclude atmospheric oxygen.

The acyl halides (IV) used as starting material are known substances,some of which are available commercially, or can be prepared analogouslyto known compounds.

A method for the preparation of metalated alkylphosphines is, forexample, the reaction of suitable alkylphosphines with the correspondingalkali metal, alkali metal hydride or an alkyl-lithium compound.

Compounds of the formula II, wherein R═Rb and Rb is a group of theformula

-   -   wherein    -   R₆, R₇, R₈, R₉ and R₁₀ independently of one another are        hydrogen, C₁–C₂₄alkyl;    -   C₂–C₂₄alkyl which is interrupted once or more than once by        nonconsecutive O, S or NR₁₄ and which is unsubstituted or        substituted by OH, SH; SR₁₁, or N(R₁₂)(R₁₃), OR₁₁, phenyl or        halogen;    -   are described in the German Patent Publication DE OS 10105046,        published Aug. 9, 2001.

The preparation of the compounds of formula II as described in theGerman Patent Publication DE OS 10105046 can be summarized as follows:

-   (1) Reaction of an acyl halide of the formula IV

-    in which-   A is as defined above and X is Cl or Br;    with a dimetalated arylphosphine of the formula V′

in which

-   -   R₆, R₇, R₈, R₉ and R₁₀ are as defined above and Ml is Na, Li or        K in the molar ratio 1:1; and

-   (2) where appropriate, subsequent hydrolysis if compounds of the    formula I in which M is hydrogen are to be obtained.

The starting materials are advantageously reacted in the molar ratio1:1. A slight excess of one or an other of the components, e.g. up to20%, is not critical. In this case the desired product is formed too,although the proportion of undesired byproducts may be influenced.

The reaction is advantageously carried out in a solvent. In particular,as solvents, it is possible to use ethers which are liquid atatmospheric pressure and room temperature. Examples are dimethyl ether,diethyl ether, methyl propyl ether, 1,2-dimethoxyethane,bis(2-methoxyethyl)ether, dioxane or tetrahydrofuran. Preference isgiven to using tetrahydrofuran.

The reaction temperatures are advantageously −60° C. to +120° C., e.g.−40° C. to 100° C., for example −20° C. to +80° C.

It is advisable to stir the reaction mixture.

It is advantageous to initially introduce the compound of the formula Vand to add dropwise the compound of the formula IV at the temperaturesgiven above.

Here, the compound of the formula IV can be added without a diluent orelse diluted with the reaction solvent.

If desired, the course of the reaction can be monitored using methodscustomary in the art, for example NMR, for example ³¹P-NMR,chromatography (thin-layer, HPLC, GC) etc.

In the reactions described above, it is essential to work in an inertgas atmosphere, e.g. with a protective gas such as argon or nitrogen, inorder to exclude atmospheric oxygen.

The acyl halides (IV) used as starting material are known substances,some of which are available commercially, or can be prepared by analogywith known compounds.

The preparation of the metalated arylphosphines (V′) can, for example,be carried out by reacting suitable phosphorus halides (preparation ofwhich is known and disclosed, for example, by W. Davies in J. Chem. Soc.(1935), 462 and J. Chem. Soc. (1944), 276 with the corresponding alkalimetal.

In order to prepare the compounds of formula I with x=0, the compoundsof formula II

are reacted analog as performed in the German Patent Publication DE OS10105046 with a linking compound Hal-L-[Hal]_(m) or Hal-W-L-[W-Hal]_(m)wherein L, W and Hal are as defined above and m is 1, 2 or 3. Dependingif a di-,tri-or tetravalent linking group is used, the ratio of theeducts varies from 2:1 to 4:1. A slight excess of one or the othereduct, e.g. up to 20%, is no critical. In this case the desired productis formed too, although the proportion of undesired byproducts may beinfluenced.

The compounds of formula I with x=1 and E=O are prepared by oxidation ofthe corresponding phosphines (compounds of formula I with x=0).

The oxidation of the phosphine is carried out using oxidizing agentscustomary in the art. Suitable oxidizing agents are primarily hydrogenperoxide and organic peroxy compounds, for example peracetic acid ort-butyl hydroperoxide, air or pure oxygen.

The oxidation is advantageously carried out in solution. Suitablesolvents are aromatic hydrocarbons, for example benzene, toluene,m-xylene, p-xylene, ethylbenzene or mesitylene, or aliphatichydrocarbons, e.g. alkanes and alkane mixtures, such as petroleum ether,hexane or cyclohexane. Further suitable examples are dimethyl ether,diethyl ether, methyl propyl ether, 1,2-dimethoxyethane,bis(2-methoxyethyl)ether, dioxane or tetrahydrofuran. Preference isgiven to using toluene.

The reaction temperature during the oxidation is advantageously keptbetween 0° and 120° C., preferably between 200 and 80° C.

The reaction products of the formula (I) with x=1 and E=O can beisolated and purified by customary processing measures familiar to theperson skilled in the art.

The compounds of formula I with x=1 and E=S are prepared by sulfurationof the corresponding phosphines (compounds of formula I with x=0).

The preparation of the respective sulfide is carried out by reactionwith sulfur. The compounds of formula I with x=1 and E=O are herereacted with an equimolar to 2-fold molar amount of elemental sulfure.g. without a diluent or optionally in a suitable inert organicsolvent. Examples of suitable solvents are those described for theoxidation reaction. It is, however, also possible to use, for example,aliphatic or aromatic ethers, for example dibutyl ether, dioxane,diethylene glycol dimethyl ether or diphenyl ether at temperatures from20° to 250° C., preferably 60° to 120° C. The resulting acylphosphinesulfide, or its solution is advantageously freed from any elementalsulfur which may still be present by filtration. Following removal ofthe solvent, the acylphosphine sulfide can be isolated in pure form bydistillation, recrystallization or chromatographic separation methods.

It is advantageous to carry out all of the reactions described abovewith the exclusion of air in an inert gas atmosphere, e.g. undernitrogen or argon gas. Moreover, stirring of the respective reactionmixture is advantageously appropriate.

The phosphines can either be isolated via known isolation andpurification techniques prior to the oxidation or sulfuration step orcan directly be oxidized or sulfurized without isolation.

According to the invention, the compounds of the formula I can be usedas photoinitiators for the photopolymerization of ethylenicallyunsaturated compounds or mixtures which comprise such compounds. Thecompounds of the formula I can be used in combination with otherphotoinitiators or other additives.

The invention thus also relates to photopolymerizable compositionscomprising

-   (a) at least one ethylenically unsaturated photopolymerizable    compound and-   (b) as photoinitiator, at least one compound of the formula I,    where the composition, in addition to the component (b), can also    comprise other photo-initiators (c) or other additives (d).

The unsaturated compounds can contain one or more olefinic double bonds.They can be of low molecular weight (monomeric) or relatively highmolecular weight (oligomeric). Examples of monomers with a double bondare alkyl or hydroxyalkyl acrylates or methacrylates, for example methylacrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate or2-hydroxyethyl acrylate, isobornyl acrylate, methyl methacrylate orethyl methacrylate. Also of interest are silicon- or fluorine-modifiedresins, e.g. silicone acrylates. Further examples are acrylonitrile,acrylamide, methacrylamide, N-substituted (meth)acrylamides, vinylesters, such as vinyl acetate, vinyl ethers, such as isobutyl vinylether, styrene, alkyl- and halostyrenes, N-vinypyrrolidone, vinylchloride or vinylidene chloride.

Examples of monomers having two or more double bonds are ethylene glycoldiacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate,hexamethylene glycol diacrylate or bisphenol A diacrylate,4,4′-bis(2-acryloyloxyethoxy)diphenylpropane, trimethylolpropanetriacrylate, pentaerythritol triacrylate or tetraacrylate, vinylacrylate, divinylbenzene, divinyl succinate, diallyl phthalate, triallylphosphate, triallyl isocyanurate or tris(2-acryloylethyl)isocyanurate.

Examples of higher molecular weight (oligomeric) polyunsaturatedcompounds are acrylicized epoxy resins, polyurethanes, polyethers andpolyesters which are acrylicized or contain vinyl ether or epoxy groups.Further examples of unsaturated oligomers are unsaturated polyesterresins which are mostly prepared from maleic acid, phthalic acid and oneor more diols and have molecular weights of from about 500 to 3,000. Inaddition, it is also possible to use vinyl ether monomers and oligomers,and maleate-terminated oligomers having polyester, polyurethane,polyether, polyvinyl ether and epoxy main chains. In particular,combinations of oligomers which carry vinyl ether groups and polymers asdescribed in WO 90/01512 are highly suitable. However, copolymers ofvinyl ether and maleic acid-functionalized monomers are also suitable.Such unsaturated oligomers may also be referred to as prepolymers.

Examples of particularly suitable compounds are esters of ethylenicallyunsaturated carboxylic acids and polyols or polyepoxides, and polymerscontaining ethylenically unsaturated groups in the chain or inside-groups, for example unsaturated polyesters, polyamides andpolyurethanes and copolymers thereof, alkyd resins, polybutadiene andbutadiene copolymers, polyisoprene and isoprene copolymers, polymers andcopolymers containing (meth)acrylic groups in side chains, and mixturesof one or more such polymers.

Examples of unsaturated carboxylic acids are acrylic acid, methacrylicacid, crotonic acid, itaconic acid, cinnamic acid, unsaturated fattyacids such as linolenic acid or oleic acid. Preference is given toacrylic acid and methacrylic acid.

Suitable polyols are aromatic and, in particular, aliphatic andcycloaliphatic polyols. Examples of aromatic polyols are hydroquinone,4,4′-dihydroxydiphenyl, 2,2-di(4-hydroxyphenyl)propane, and alsonovolaks and resols. Examples of polyepoxides are those based on saidpolyols, particularly aromatic polyols and epichlorohydrins. Inaddition, polymers and copolymers which contain hydroxyl groups in thepolymer chain or in side groups, for example polyvinyl alcohol andcopolymers thereof or hydroxyalkyl polymethacrylates or copolymersthereof, are also suitable as polyols. Further suitable polyols areoligoesters containing hydroxyl end-groups.

Examples of aliphatic and cycloaliphatic polyols are alkylenediolshaving, preferably, 2 to 12 carbon atoms, such as ethylene glycol, 1,2-or 1,3-propanediol, 1,2-, 1,3- or 1,4-butanediol, pentanediol,hexanediol, octanediol, dodecanediol, diethylene glycol, triethyleneglycol, polyethylene glycols having molecular weights of, preferably,200 to 1,500, 1,3-cyclopentanediol, 1,2-, 1,3- or 1,4-cyclohexanediol,1,4-dihydroxymethylcyclohexane, glycerol, tris(β-hydroxyethyl)amine,trimethylolethane, trimethylolpropane, pentaerythritol,dipentaerythritol and sorbitol.

The polyols may be partially or completely esterified using one ordifferent unsaturated carboxylic acids, where the free hydroxyl groupsin partial esters may be modified, e.g. etherified or esterified withother carboxylic acids.

Examples of esters are:

trimethylolpropane triacrylate, trimethylolethane triacrylate,trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate,tetramethylene glycol dimethacrylate, triethylene glycol dimethacrylate,dipropylenglycoldiacrylat, tripropylenglycoldiacrylat, tetraethyleneglycol diacrylate, pentaerythritol diacrylate, pentaerythritoltriacrylate, pentaerythritol tetraacrylate, dipentaerythritoldiacrylate, dipentaerythritol triacrylate, dipentaerythritoltetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritolhexaacrylate, tripentaerythritol octaacrylate, pentaerythritoldimethacrylate, pentaerythritol trimethacrylate, dipentaerythritoldimethacrylate, dipentaerythritol tetramethacrylate, tripentaerythritoloctamethacrylate, pentaerythritol diitaconate, dipentaerythritoltrisitaconate, dipentaerythritol pentaitaconate, dipentaerythritolhexaitaconate, ethylene glycol diacrylate, 1,3-butanediol diacrylate,1,3-butanediol dimethacrylate, 1,4-butanediol diitaconate, sorbitoltriacrylate, sorbitol tetraacrylate, pentaerythritol-modifiedtriacrylate, sorbitol tetramethacrylate, sorbitol pentaacrylate,sorbitol hexaacrylate, oligoester acrylates and methacrylates, glyceroldi- and triacrylate, 1,4-cyclohexane diacrylate, bisacrylates andbismethacrylates of polyethylene glycol having molecular weights of from200 to 1,500, or mixtures thereof.

Furthermore the following esters are suitable: 1,6-hexanedioldiacrylate, glycerine ethoxylate triacrylate, glycerine propoxylatetriacrylate, trimethylolpropane ethoxylate triacrylate,trimethylolpropane propoxylate triacrylate, pentaerythritethoxylatetetraacrylate, pentaerythritpropoxylate triacrylate,pentaerythritpropoxylate tetraacrylate, neopentylglycolethoxylatediacrylate, neopentylglycolpropoxylate diacrylate.

Also suitable as component (a) are the amides of identical or differentunsaturated carboxylic acids of aromatic, cycloaliphatic and aliphaticpolyamines having, preferably, 2 to 6, particularly 2 to 4, aminogroups. Examples of such polyamines are ethylenediamine, 1,2- or1,3-propylenediamine, 1,2-, 1,3- or 1,4-butylenediamine,1,5-pentylenediamine, 1,6-hexylenediamine, octylenediamine,dodecylenediamine, 1,4-diaminocyclohexane, isophoronediamine,phenylenediamine, bisphenylenediamine, di-β-aminoethyl ether,diethylenetriamine, triethylenetetramine, di(β-aminoethoxy)ethane ordi(β-aminopropoxy)ethane. Further suitable polyamines are polymers andcopolymers with or without additional amino groups in the side chain andoligoamides containing amino end groups. Examples of such unsaturatedamides are: methylenebisacrylamide, 1,6-hexamethylenebisacrylamide,diethylenetriaminetrismethacrylamide, bis(methacrylamidopropoxy)ethane,β-methacrylamidoethyl methacrylate, N[(β-hydroxyethoxy)ethyl]acrylamide.

Suitable unsaturated polyesters and polyamides are derived, for example,from maleic acid and diols or diamines. Some of the maleic acid may bereplaced by other dicarboxylic acids. They can be used together withethylenically unsaturated comonomers, e.g. styrene. The polyesters andpolyamides may also be derived from dicarboxylic acids and ethylenicallyunsaturated diols or diamines, particularly from relatively long chaincompounds containing, for example, 6 to 20 carbon atoms. Examples ofpolyurethanes are those constructed from saturated or unsaturateddiisocyanates and unsaturated or saturated diols.

Polybutadiene and polyisoprene and copolymers thereof are known.Suitable comonomers are, for example, olefins, such as ethylene,propene, butene, hexene, (meth)acrylates, acrylonitrile, styrene orvinyl chloride. Polymers containing (meth)acrylate groups in the sidechain are likewise known. These may, for example, be products of thereaction of novolak-based epoxy resins with (meth)acrylic acid, homo- orcopolymers of vinyl alcohol or hydroxyalkyl derivatives thereof whichhave been esterified using (meth)acrylic acid, or homo- and copolymersof (meth)acrylates which have been esterified usinghydroxyalkyl(meth)acrylates.

The photopolymerizable compounds may be used on their own or in anydesired mixtures. Preference is given to using mixtures of polyol(meth)acrylates.

It is also possible to add binders to the compositions according to theinvention; this is particularly advantageous if the photopolymerizablecompounds are liquid or viscose substances. The amount of binder may,for example, be 5–95% by weight, preferably 10–90% by weight andparticularly 40–90% by weight, based on the total solids. The binder ischosen depending on the field of application and on the propertiesrequired therefore, such as the facility for development in aqueous ororganic solvent systems, adhesion to substrates and sensitivity tooxygen.

Examples of suitable binders are polymers having a molecular weight offrom about 5,000–2,000,000, preferably 10,000–1,000,000. Examples are:homo- and copolymeric acrylates and methacrylates, e.g. copolymers ofmethyl methacrylate/ethyl acrylate/methacrylic acid, poly(alkylmethacrylates), poly(alkyl acrylates); cellulose esters and celluloseethers, such as cellulose acetate, cellulose acetate butyrate,methylcellulose, ethylcellulose; polyvinylbutyral, polyvinylformal,cyclized rubber, polyethers, such as polyethylene oxide, polypropyleneoxide, polytetrahydroturan; polystyrene, polycarbonate, polyurethane,chlorinated polyolefins, polyvinyl chloride, copolymers of vinylchloride/vinylidene chloride, copolymers of vinylidene chloride withacrylonitrile, methyl methacrylate and vinyl acetate, polyvinyl acetate,copoly(ethylene/vinyl acetate), polymers such as polycaprolactam andpoly(hexamethyleneadipamide), and polyesters such as poly(ethyleneglycol terephthalate) and poly(hexamethylene glycol succinate).

The unsaturated compounds can also be used in mixtures withnon-photopolymerizable film-forming components. These may, for example,be physically drying polymers or solutions thereof in organic solvents,for example nitrocellulose or cellulose acetobutyrate. However, they mayalso be chemically or thermally curable resins, for examplepolyisocyanates, polyepoxides or melamine resins. The co-use ofthermally curable resins is of importance for use in so-called hybridsystems, which are photopolymerized in a first stage and are crosslinkedby thermal aftertreatment in a second stage.

The photoinitiators according to the invention are also suitable asinitiators for the curing of oxidatively drying systems, as aredescribed, for example, in Lehrbuch der Lacke und Beschichtungen VolumeIII, 296–328, Verlag W. A. Colomb in Heenemann GmbH,Berlin-Oberschwandorf (1976).

Apart from the photoinitiator, the photopolymerizable mixtures can alsocontain various additives (d). Examples thereof are thermal inhibitors,which are intended to prevent premature polymerization, for examplehydroquinone, hydroquinone derivatives, p-methoxyphenol, β-naphthol orsterically hindered phenols, for example 2,6-di(tert-butyl)-p-cresol. Toincrease the storage stability in the dark it is possible, for example,to use copper compounds, such as copper naphthenate, stearate oroctoate, phosphorus compounds, for example triphenylphosphine,tributylphosphine, triethyl phosphite, triphenyl phosphite or tribenzylphosphite, quaternary ammonium compounds, for exampletetramethylammonium chloride or trimethylbenzylammonium chloride, orhydroxylamine derivatives, for example N-diethylhydroxylamine. In orderto exclude atmospheric oxygen during the polymerization, it is possibleto add paraffin or similar wax-like substances which migrate to thesurface at the start of the polymerization due to their lack ofsolubility in the polymers, and form a transparent surface layer whichprevents the entry of air. It is likewise possible to apply anoxygen-impermeable layer. Light protection agents which may be used areUV absorbers, for example those of the hydroxyphenylbenzotriazol,hydroxyphenylbenzophenone, oxalamide or hydroxyphenyl-s-triazine type.The compounds can be used individually or as mixtures, with or withoutthe use of sterically hindered amines (HALS).

Examples of such UV absorbers and light protection agents are

-   1. 2-(2′-Hydroxyphenyl)benzotriazoles, for example    2-(2′-hydroxy-5′-methylphenyl)benzotriazole,    2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)benzotriazole,    2-(5′-tert-butyl-2′-hydroxyphenyl)benzotriazole,    2-(2′-hydroxy-5′-(1,1,3,3-tetramethylbutyl)phenyl)benzotriazole,    2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)-5-chlorobenzotriazole,    2-(3′-tert-butyl-2′-hydroxy-5′-methylphenyl)-5-chlorobenzotriazole,    2-(3′-sec-butyl-5′-tert-butyl-2′-hydroxyphenyl)benzotriazole,    2-(2′-hydroxy4′-octoxyphenyl)benzotriazole,    2-(3′,5′-di-tert-amyl-2′-hydroxyphenyl)benzotriazole,    2-(3′,5′-bis(α,α-dimethylbenzyl)-2′-hydroxyphenyl)benzotriazole,    mixture of    2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)-5-chlorobenzotriazole,    2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxyphenyl)-5-chlorobenzotriazole.    2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)-5-chlorobenzotriazole,    2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)benzotriazole,    2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)benzotriazole,    2-(3′-tert-butyl-5′-[2-(2-ethyl-hexyloxy)carbonylethyl]-2′-hydroxyphenyl)benzotriazole,    2-(3′-dodecyl-2′-hydroxy-5′-methylphenyl)benzotriazole, and    2-(3′-tert-butyl-2′-hydroxy-5′-(2-isooctyloxycarbonylethyl)phenylbenzotriazole,    2,2′-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-benzotriazol-2-yl    phenol]; transesterification product of    2-[3′-tert-butyl-5′-(2-methoxycarbonylethyl)-2′-hydroxyphenyl]-benzotriazole    with polyethylene glycol 300; [R—CH₂CH₂—COO(CH₂)₃]₂— where    R=3′-tert-butyl-4′-hydroxy-5′-2H-benzotriazol-2-yl phenyl.-   2. 2-Hydroxybenzophenones, for example the 4-hydroxy, 4-methoxy,    4-octoxy, 4-decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2′,4′-trihydroxy    and 2′-hydroxy-4,4′-dimethoxy derivatives.-   3. Esters of unsubstituted or substituted benzoic acids, for example    4-tert-butyl-phenyl salicylate, phenyl salicylate, octylphenyl    salicylate, dibenzoylresorcinol, bis(4-tert-butylbenzoyl)resorcinol,    benzoylresorcinol, 2,4-di-tert-butylphenyl    3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl    3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl    3,5-di-tert-butyl-4-hydroxybenzoate,    2-methyl-4,6-di-tert-butylphenyl    3,5-di-tert-butyl-4-hydroxybenzoate.-   4. Acrylates, for example ethyl and isooctyl    α-cyano-β,β-diphenylacrylate, methyl α-carbomethoxycinnamate, methyl    and butyl α-cyano-β-methyl-p-methoxycinnamate, methyl    α-carbomethoxy-p-methoxycinnamate and    N-(β-carbomethoxy-β-cyanovinyl)-2-methyl-indoline.-   5. Sterically hindered amines, for example    bis(2,2,6,6-tetramethylpiperidyl)sebacate,    bis(2,2,6,6-tetramethylpiperidyl)succinate,    bis(1,2,2,6,6-pentamethylpiperidyl)sebacate,    bis(1,2,2,6,6-pentamethylpiperidyl)n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate,    the product of the condensation of    1-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic    acid, the product of the condensation of    N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and    4-tert-octylamino-2,6-dichloro-1,3,5-s-triazine,    tris(2,2,6,6-tetramethyl-4-piperidyl)nitrilotriacetate,    tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetraoate,    1,1′-(1,2-ethanediyl)bis-(3,3,5,5-tetramethylpiperazinone),    4-benzoyl-2,2,6,6-tetramethylpiperidine,    4-stearyloxy-2,2,6,6-tetramethylpiperidine,    bis(1,2,2,6,6-penta-methylpiperidyl)2-n-butyl-2-(2-hydroxy-3,5-di-tert-butylbenzyl)malonate,    3-n-octyl-7,7,9,9-tetramethyl-1,3,3-triazaspiro[4.5]decane-2,4-dione,    bis(1-octyloxy-2,2,6,6-tetra-methylpiperidyl)sebacate,    bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)succinate, the product    of the condensation of    N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylene-diamine and    4-morpholino-2,6-dichloro-1,3,5-triazine, the product of the    condensation of    2-chloro-4,6-di(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)1,3,5-triazine    and 1,2-bis(3-aminopropylamino)ethane, the product of the    condensation of    2-chloro-4,6-di(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triazine    and 1,2-bis(3-aminopropylamino)ethane,    8-acetyl-3-dodecyl-7,7,9,9,-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione,    3-dodecyl-1-(2,2,6,6-tetramethyl-4-piperidyl)pyrrolidine-2,5-dione,    3-dodecyl-1-(1,2,2,6,6-pentamethyl-4-piperidyl)pyrrolidine-2,5-dione,    2,4-bis[N-(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)-N-butylamino]-6-(2-hydroxyethyl)amino-1,3,5-triazine,    the product of the condensation of    2,4-bis[1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-chloro-s-triazine    and N,N′-bis(3-aminopropyl)ethylenediamine.

6. Oxalamides, for example 4,4′-dioctyloxyoxanilide,2,2′-diethoxyoxanilide, 2,2′-dioctyloxy-5,5′-di-tert-butyloxanilide,2,2′-didodecyloxy-5,5′-di-tert-butyloxanilide,2-ethoxy-2′-ethyloxanilide, N,N′-bis(3-dimethylaminopropyl)oxalamide,2-ethoxy-5-tert-butyl-2′-ethyloxanilide and mixtures thereof with2-ethoxy-2′-ethyl-5,4′-di-tert-butyloxanilide, and mixtures of o- andp-methoxy- and of o- and p-ethoxy-disubstituted oxanilides.

7. 2-(2-Hydroxyphenyl)-1,3,5-triazines, for example

-   -   2,4,6-tris(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine,    -   2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,    -   2-(2,4-dihydroxyphenyl)-4,6-bis(2,5-dimethylphenyl)-1,3,5-triazine,    -   2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazine,    -   2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1,3,5-triazine,    -   2-(2-hydroxy-4-dodecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,    -   2-[2-hydroxy-4-(2-hydroxy-3-butyloxypropyloxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,    -   2-[2-hydroxy-4-(2-hydroxy-3-octyloxy-propytoxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine        and    -   2-[4-dodecyl/tridecyloxy(2-hydroxypropyl)oxy-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine.

8. Phosphites and phosphonites, for example triphenyl phosphite,diphenyl alkylphosphites, phenyl dialkylphosphites,tris(nonylphenyl)phosphite, trilauryl phosphite, trioctadecyl phosphite,distearyl pentaerythritol diphosphite,tris(2,4-di-tert-butylphenyl)phosphite, diisodecylpentaerythritoldiphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite,bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite,bisisodecyloxy-pentaerythritol diphosphite,bis(2,4-di-tert-butyl-6-methylphenyl)pentaerythritol diphosphite,bis(2,4,6-tri-tert-butylphenyl)pentaerythritol diphosphite,tristearylsorbitol triphosphite,tetrakis-(2,4-di-tert-butylphenyl)-4,4′-biphenylenediphosphonite,6-isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-dibenz[d,g]-1,3,2-dioxaphosphocine,6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-dibenz-[d,g]-1,3,2-dioxaphosphocine,bis(2,4-di-tert-butyl-6-methylphenyl)methylphosphite, andbis(2,4-di-tert-butyl-6-methylphenyl)ethylphosphite.

Examples of UV absorbers and light protection agents suitable ascomponent (d) are also “Krypto-UVA”, as are described, for example, inEP 180548. It is also possible to use latent UV absorbers, as described,for example, by Hida et al. in RadTech Asia 97, 1997, page 212.

It is also possible to use additives customary in the art, for exampleantistats, levelling auxiliaries and adhesion improvers.

To accelerate the photopolymerization it is possible to add, as furtheradditives (d), a large number of amines, for example triethanolamine,N-methyldiethanolamine, ethyl p-dimethylaminobenzoate or Michlersketone. The action of the amines can be intensified by the addition ofaromatic ketones, e.g. of the benzophenone type. Examples of amineswhich can be used as oxygen scavengers are substitutedN,N-dialkylanilines, as described in EP 339841. Other accelerators,coinitiators and autoxidators are thiols, thioethers, disulfides andphosphines, as described, for example, in EP 438123 and GB 2180358.

It is also possible to add chain transfer reagents customary in the artto the compositions according to the invention. Examples thereof aremercaptans, amines and benzothiazols.

The photopolymerization can also be accelerated by the addition ofphotosensitizers as further additives (d); these shift or broaden thespectral sensitivity. These are, in particular, aromatic carbonylcompounds, for example benzophenone, thioxanthone, in particular alsoisopropylthioxanthone, anthraquinone and 3-acylcoumarin derivatives,terphenyls, styryl ketones, and 3-(aroylmethylene)thiazolines,camphorquinone, but also eosin, rhodamine and erythrosine dyes.

As photosensitizers, it is also possible, for example, to consider theamines given above.

Further examples of such photosensitizers are

1. Thioxanthones

thioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone,2-dodecylthioxanthone, 2,4-di-ethylthioxanthone,2,4-dimethylthioxanthone, 1-methoxycarbonylthioxanthone,2-ethoxy-carbonylthioxanthone, 3-(2-methoxyethoxycarbonyl)thioxanthone,4-butoxycarbonylthioxanthone, 3-butoxycarbonyl-7-methylthioxanthone,1-cyano-3-chlorothioxanthone, 1-ethoxycarbonyl-3-chlorothioxanthone,1-ethoxycarbonyl-3-ethoxythioxanthone,1-ethoxycarbonyl-3-aminothioxanthone,1-ethoxycarbonyl-3-phenylsulfurylthioxanthone,3,4-di-[2-(2-methoxyethoxy)ethoxycarbonyl]thioxanthone,1-ethoxycarbonyl-3-(1-methyl-1-morpholinoethyl)thioxanthone,2-methyl-6-dimethoxymethylthioxanthone,2-methyl-6-(1,1-dimethoxybenzyl)thioxanthone,2-morpholinomethylthioxanthone, 2-methyl-6-morpholinomethylthioxanthone,n-allylthioxanthone-3,4-dicarboximide,n-octylthioxanthone-3,4-dicarboximide,N-(1,1,3,3-tetra-methylbutyl)thioxanthone-3,4-dicarboximide,1-phenoxythioxanthone, 6-ethoxycarbonyl-2-methoxythioxanthone,6-ethoxycarbonyl-2-methylthioxanthone, thioxanthone-2-polyethyleneglycol ester,2-hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthon-2-yloxy)-N,N,N-trimethyl-1-propanaminiumchloride;

2. Benzophenones

benzophenone, 4-phenylbenzophenone, 4-methoxybenzophenone,4,4′-dimethoxybenzophenone, 4,4′-dimethylbenzophenone,4,4′-dichlorobenzophenone, 4,4′-dimethylaminobenzophenone,4,4′-diethylaminobenzophenone, 4-methylbenzophenone,2,4,6-trimethylbenzophenone, 4-(4-methylthiophenyl)benzophenone,3,3′-dimethyl-4-methoxybenzophenone, methyl-2-benzoylbenzoate,4-(2-hydroxyethylthio)benzophenone, 4-(4-tolylthio)benzophenone,4-benzoyl-N,N,N-trimethylbenzenemethanaminium chloride,2-hydroxy-3-(4-benzoylphenoxy)-N,N,N-trimethyl-1-propanaminium chloridemonohydrate, 4-(13-acryloyl-1,4,7,10,13-pentaoxatridecyl)benzophenone,4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2-propenyl)oxy]ethylbenzenemethanaminiumchloride;

3. 3-Acylcoumarins

3-benzoylcoumarin, 3-benzoyl-7-methoxycoumarin,3-benzoyl-5,7-di(propoxy)coumarin, 3-benzoyl-6,8-dichlorocoumarin,3-benzoyl-6-chlorocoumarin, 3,3′-carbonylbis[5,7-di(propoxy)coumarin],3,3′-carbonylbis(7-methoxycoumarin),3,3′-carbonylbis(7-diethylaminocoumarin), 3-isobutyroylcoumarin,3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-5,7-diethoxycoumarin,3-benzoyl-5,7-dibutoxycoumarin, 3-benzoyl-5,7-di(methoxyethoxy)coumarin,3-benzoyl-5,7-di(allyloxy)coumarin, 3-benzoyl-7-dimethylaminocoumarin,3-benzoyl-7-diethylaminocoumarin, 3-isobutyroyl-7-dimethylaminocoumarin,5,7-dimethoxy-3-(1-naphthoyl)coumarin,5,7-dimethoxy-3-(1-naphthoyl)coumarin, 3-benzoylbenzo[f]coumarin,7-diethylamino-3-thienoylcoumarin,3-(4-cyanobenzoyl)-5,7-dimethoxycoumarin;

4. 3-(Aroylmethylene)thiazolines

3-Methyl-2-benzoylmethylene-β-naphthothiazoline,3-methyl-2-benzoylmethylenebenzothiazoline,3-ethyl-2-propionylmethylene-β-naphthothiazoline;

5. Anthracenes:

9,10-dimethoxy-anthracene, 9,10-diethoxy-anthracene,9,10-dimethoxy-2-ethyl-anthracene,

6. Other Carbonyl Compounds

Acetophenone, 3-methoxyacetophenone, 4-phenylacetophenone, benzil,2-acetylnaphthalene, 2-naphthaldehyde, 9,10-anthraquinone, 9-fluorenone,dibenzosuberone, xanthone,2,5-bis(4-diethylaminobenzylidene)cyclopentanone,α-(para-dimethylaminobenzylidene)ketones, such as2-(4-dimethylaminobenzylidene)indan-1-one or3-(4-dimethylaminophenyl)-1-indan-5-ylpropenone,3-phenylthiophthalimide, N-methyl-3,5-di(ethylthio)phthalimide.

The curing process can also be aided, in particular, by pigmentedcompositions (e.g. with titanium dioxide), also by the addition asadditional additive (d) of a component which forms the radicals underthermal conditions, for example an azo compound, such as2,2′-azobis-(4-methoxy-2,4-dimethylvaleronitrile), a triazene, diazosulfide, pentazadiene or a peroxy compound, for example hydroperoxide orperoxycarbonate, e.g. t-butyl hydroperoxide, as described, for example,in EP 245639.

As further additive (d), the compositions according to the invention canalso comprise a photoreproducible dye, for example xanthene,benzoxanthene, benzothioxanthene, thiazine, pyronine, porphyrin oracridine dyes, or a radiation-cleavable trihalomethyl compound. Similarcompositions are described, for example, in EP 445624.

Depending on the intended use, further customary additives (d) areoptical brighteners, fillers, pigments, both white and colouredpigments, dyes, antistats, wetting agents or levelling auxiliaries.

For the curing of thick and pigmented coatings, the addition ofmicroglass beads or pulverized glass fibres, as described, for example,in U.S. Pat. No. 5,013,768, is suitable.

The formulations can also comprise dyes or white or coloured pigments.Depending on the intended use, it is possible to use both inorganic andorganic pigments. Such additives are known to the person skilled in theart, examples being titanium dioxide pigments, e.g. of the rutile oranatase type, carbon black, zinc oxide, such as zinc white, iron oxides,such as iron oxide yellow, iron oxide red, chromium yellow, chromiumgreen, nickel, titanium yellow, ultra-marine blue, cobalt blue, bismuthvanadate, cadmium yellow or cadmium red. Examples of organic pigmentsare mono- or bisazo pigments, and metal complexes thereof,phthalocyanine pigments, polycyclic pigments, for example perylene,anthraquinone, thioindigo, quinacridone or triphenylmethane pigments,and diketopyrrolopyrrole, isoindolinone, e.g. tetra-chloroisoindolinone,isoindoline, dioxazine, benzimidazolone and quinophthalone pigments.

The pigments can be used individually or else as mixtures in theformulations. Depending on the intended use, the pigments are added tothe formulations in amounts customary in the art, for example in anamount of from 0.1 to 60% by weight, 0.1 to 30% by weight or 10 to 30%by weight, based on the total composition.

The formulations can, for example, also comprise organic dyes from verydiverse classes. Examples are azo dyes, methine dyes, anthraquinone dyesor metal complex dyes. Customary concentrations are, for example, 0.1 to20%, in particular 1 to 5%, based on the total compositions.

Depending on the formulation used, compounds can also neutralize theacids, in particular amines are used as stabilizers. Suitable systemsare described, for example, in JP-A 11-199610. Examples are pyridine andderivatives thereof, N-alkylanilines or N,N-dialkylanilines, pyrazinederivatives, pyrrol derivatives, etc.

The choice of additives depends on the field of application in questionand the properties desired for this field. The above-described additives(d) are customary in the art and are accordingly used in amountscustomary in the art.

The invention also provides compositions comprising, as components (a),at least one ethylenically unsaturated photopolymerizable compound whichis emulsified or dissolved in water.

Such radiation-curable aqueous prepolymer dispersions are availablecommercially in many variations. This is understood as meaning adispersion of water and at least one prepolymer dispersed therein. Theconcentration of the water in these systems is, for example, 2 to 80% byweight, in particular 30 to 60% by weight. The radiation-curableprepolymers or prepolymer mixture is present, for example, inconcentrations of from 95 to 20% by weight, in particular 70 to 40% byweight. In these compositions, the total of the percentages given forwater and prepolymers is in each case 100, the auxiliaries and additivesbeing added in varying amounts, depending on the intended use.

The radiation-curable film-forming prepolymers which are dispersed, andoften also dissolved, in water are mono- or polyfunctional ethylenicallyunsaturated prepolymers which can be initiated by free radicals and areknown per se for aqueous prepolymer dispersions, which have, forexample, a content of from 0.01 to 1.0 mol per 100 g of prepolymer ofpolymerizable double bonds, and also an average molecular weight of, forexample, at least 400, in particular from 500 to 10,000. However,depending on the intended use, prepolymers with higher molecular weightsare also suitable.

Polyesters containing polymerizable C—C double bonds and having an acidnumber of at most 10, polyethers containing polymerizable C—C doublebonds, hydroxyl-containing products of the reaction of a polyepoxidecontaining at least two epoxide groups per molecule with at least oneα,β-ethylenically unsaturated carboxylic acid,polyurethane(meth)acrylates, and acrylic copolymers containingα,β-ethylenically unsaturated acrylic radicals, as are described in EP12339. Mixtures of these prepolymers can likewise be used. Also suitableare the polymerizable prepolymers described in EP 33896, which arethioether adducts of polymerizable prepolymers having an averagemolecular weight of at least 600, a carboxyl group content of from 0.2to 15% and a content of from 0.01 to 0.8 mol of polymerizable C—C doublebonds per 100 g of prepolymer. Other suitable aqueous dispersions basedon specific (meth)acrylic alkyl ester polymers are described in EP41125, and suitable water-dispersible, radiation-curable prepolymers ofurethane acrylates can be found in DE 2936039.

As further additives, these radiation-curable aqueous prepolymerdispersions can also comprise the above-described additional additives(d), i.e., for example, dispersion auxiliaries, emulsifiers,antioxidants, light stabilizers, dyes, pigments, fillers, e.g. talc,gypsum, silica, rutile, carbon black, zinc oxide, iron oxides, reactionaccelerators, levelling agents, lubricants, wetting agents, thickeners,matting agents, antifoams and other auxiliaries customary in surfacecoating technology. Suitable dispersion auxiliaries are water-solublehigh molecular weight organic compounds having polar groups, for examplepolyvinyl alcohols, polyvinylpyrrolidone or cellulose ethers.Emulsifiers which may be used are nonionic, and, where appropriate, alsoionic, emulsifiers.

The photoinitiators of the formula I according to the invention can alsobe dispersed as such in aqueous solutions and added in this dispersedform to the mixtures to be cured. Treated with suitable nonionic or,where appropriate, also ionic, emulsifiers, the compounds of the formulaI according to the invention can be incorporated by mixing and e.g.binding into water. This produces stable emulsions which can be used assuch as photoinitiators, in particular for aqueous photocurable mixturesas described above.

In certain cases, it may be advantageous to use mixtures of two or moreof the photo-initiators according to the invention. It is of course alsopossible to use mixtures with known photoinitiators, e.g. mixtures withcamphorquinone, benzophenone, benzophenone derivatives, acetophenone,acetophenone derivatives, for example α-hydroxycycloalkyl phenyl ketonesor 2-hydroxy-2-methyl-1-phenylpropanone, dialkoxyacetophenones,α-hydroxy or α-aminoacetophenones, for example4-methylthiobenzoyl-1-methyl-1-morpholinoethane,4-morpholinobenzoyl-1-benzyl-1-dimethylaminopropane,4-aroyl-1,3-dioxolanes, benzoin alkyl ethers and benzil ketals, forexample benzil dimethyl ketal, phenyl glyoxalates and derivativesthereof, dimeric phenyl glyoxalates, peresters, e.g.benzophenonetetracarboxylic peresters, as described, for example, in EP126541, monoacylphosphine oxides, for example(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bisacylphosphine oxides,for example bis(2,6-dimethoxybenzoyl)(2,4,4-trimethylpent-1-yl)phosphineoxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide orbis(2,4,6-trimethylbenzoyl)(2,4-dipentoxyphenyl)phosphine oxide,trisacylphosphine oxides, halomethyltriazines, e.g.2-[2-(4-methoxyphenyl)vinyl]-4,6-bistrichloromethyl-[1,3,5]triazine,2-(4-methoxyphenyl)-4,6-bis-trichloromethyl-[1,3,5]triazine,2-(3,4-dimethoxyphenyl)-4,6-bistrichloromethyl-[1,3,5]triazine,2-methyl-4,6-bistrichloromethyl-[1,3,5]triazine,hexaarylbisimidazole/coinitiator systems, e.g.ortho-chlorohexaphenylbisimidazole in combination with2-mercaptobenzothiazole; ferrocenium compounds or titanocenes, forexample dicyclopentadienylbis(2,6-difluoro-3-pyrrolophenyl)titanium.Coinitiators which may also be used are borate compounds.

In the case of the use of the photoinitiators according to the inventionin hybrid systems, in this connection mixtures of free-radically andcationically curing systems are thus intended, in addition to thefree-radical curing agents according to the invention, cationicphotoinitiators, for example benzoyl peroxide (other suitable peroxidesare described in U.S. Pat. No. 4,950,581, column 19, lines 17–25),aromatic sulfonium, phosphonium or iodonium salts, as described, forexample in U.S. Pat. No. 4,950,581, column 18, line 60 to column 19,line 10, or cyclopentadienylareneiron(II) complex salts, e.g.(η⁶-Isopropylbenzene)(η⁵-cyclopentadienyl)iron(II) hexafluorophosphate,are used.

The invention also provides compositions in which the additionalphotoinitiators (c) are compounds of the formula VIII, IX, X, XI, XII,XIII or mixtures thereof,

in which

-   R₂₅ is hydrogen, C₁–C₁₈alkyl, C₁–C₁₈alkoxy, —OCH₂CH₂—OR₂₉,    morpholino, SCH₃, a group

-    or a group

-   n has a value from 2 to 10;-   G₁ and G₂ independently of one another are end-groups of the    polymeric unit, in particular hydrogen or CH₃;-   R₂₆ is hydroxyl, C₁–C₁₆alkoxy, morpholino, dimethylamino or    —O(CH₂CH₂O)_(m)—C₁–C₁₆alkyl;-   R₂₇ and R₂₈ independently of one another are hydrogen, C₁–C₆alkyl,    phenyl, benzyl, C₁–C₁₆alkoxy or —O(CH₂CH₂O)_(m)—C₁–C₁₆alkyl, or R₂₇    and R₂₈ together with the carbon atom to which they are bonded form    a cyclohexyl ring; where R₂₆, R₂₇ and R₂₈ are not all C₁–C₁₆alkoxy    or —O(CH₂CH₂O)_(m)—C₁–C₁₆alkyl at the same time, and-   m is a number from 1–20; and-   R₂₉ is hydrogen,

-   R₃₀ and R₃₂ independently of one another are hydrogen or methyl;-   R₃₁ is hydrogen, methyl or phenylthio, where the phenyl ring of the    phenylthio radical is unsubstituted or substituted by C₁–C₄alkyl in    the 4-, 2-, 2,4- or 2,4,6-position;-   R₃₃ and R₃₄ independently of one another are C₁–C₂₀alkyl,    cyclohexyl, cyclopentyl, phenyl, naphthyl or biphenyl, where these    radicals are unsubstituted or are substituted by halogen,    C₁–C₁₂alkyl or C₁–C₁₂-alkoxy, or R₃₃ is an 8- or N-containing 5- or    6-membered heterocyclic ring, or are

-   R₃₅ is cyclohexyl, cyclopentyl, phenyl, naphthyl or biphenyl, these    radicals being unsubstituted or substituted by halogen, C₁–C₄alkyl    or C₁–C₄alkoxy, or R₃₅ is an S— or N-containing 5- or 6-membered    heterocyclic ring;-   R₃₆ and R₃₇ independently of one another are unsubstituted    cyclopentadienyl or cyclopentadienyl substituted once, twice or    three times by C₁–C₁₈alkyl, C₁–C₁₈alkoxy, cyclopentyl, cyclohexyl or    halogen; and-   R₃₈ and R₃₉ independently of one another are phenyl which is    substituted in at least one of the two ortho positions relative to    the titanium-carbon bond by fluorine atoms or CF₃, and which on the    aromatic ring may contain, as further substituents, unsubstituted    pyrrolinyl or pyrrolinyl substituted by one or two C₁–C₁₂alkyl,    di(C₁–C₁₂alkyl)aminomethyl, morpholinomethyl, C₂–C₄alkenyl,    methoxymethyl, ethoxymethyl, trimethylsilyl, formyl, methoxy or    phenyl; or polyoxaalkyl, or-   R₃₈ and R₃₉ are

-   R₄₀, R₄₁ and R₄₂ independently of one another are hydrogen, halogen,    C₂–C₁₂alkenyl, C₁–C₁₂alkoxy, C₂–C₁₂alkoxy interrupted by one to four    O atoms, cycylohexyloxy, cyclopentyloxy, phenoxy, benzyloxy,    unsubstituted phenyl or phenyl substituted by C₁–C₄alkoxy, halogen,    phenylthio or C₁–C₄-alkylthio; or biphenyl, where R₄₀ and R₄₂ are    not both hydrogen at the same time and in the radical

-    at least one radical R₄₀ or R₄₂ is C₁–C₁₂alkoxy, C₂–C₁₂alkoxy    interrupted by one to four O atoms, cyclohexyloxy, cyclopentyloxy,    phenoxy or benzyloxy;-   E₁ is O, S or NR₄₃; and-   R₄₃ is C₁–C₈alkyl, phenyl or cyclohexyl,-   R₄₄ is H, C₁–C₁₂alkyl, C₁–C₁₂alkyl interrupted once or more than    once by nonconsecutive O, C₅–C₁₀cycloalkyl, benzyl or phenyl;-   R₄₅ is C₁–C₁₂alkylene, C₄–C₈-alkenylene, C₄–C₈alkynylene,    cyclohexylene, C₄–C₄₀alkylene interrupted one or more times by —O—,    —S— or —NR₄₆—, or is phenylene, or-   R₄₅ is a group selected from

-   R₄₆ is hydrogen, C₁–C₁₂alkyl or phenyl.

R₂₅ as C₁–C₁₈alkyl can have the same meanings as described for thecompounds of the formulae I, II or III. Also, R₂₇ and R₂₈ as C₁–C₆alkyland R₂₆ as C₁–C₄alkyl can have the same meanings as described aboveapart from the respective number of carbon atoms.

C₁–C₁₈alkoxy is, for example, branched or unbranched alkoxy, for examplemethoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy,tert-butoxy, pentoxy, hexyloxy, heptyloxy, octyloxy,2,4,4-trimethylpent-1-yloxy, 2-ethylhexyloxy, nonyloxy, decyloxy,dodecyloxy or octadecyloxy.

C₂–C₁₂alkoxy has the meanings given above apart from the correspondingnumber of carbon atoms.

C₁–C₁₆alkoxy has the same meanings as described above apart from thecorresponding number of carbon atoms, and decyloxy, methoxy and ethoxyare preferred, in particular methoxy and ethoxy.

The radical —O(CH₂CH₂O)_(m)—C₁–C₁₆alkyl stands for 1 to 20 consecutiveethylene oxide units whose chain ends with a C₁–C₁₆alkyl. Preferably, mis 1 to 10, e.g. 1 to 8, in particular 1 to 6.

Preferably, the ethylene oxide unit chain is terminated with aC₁–C₁₀alkyl, e.g. C₁–C₈alkyl, in particular with a C₁–C₄alkyl.

R₃₁ as a substituted phenylthio ring is, preferably, p-tolylthio.

R₃₃ and R₃₄ as C₁–C₂₀alkyl are linear or branched and are, for example,C₁–C₁₂alkyl, C₁–C₈alkyl, C₁–C₆alkyl or C₁–C₄alkyl. Examples are methyl,ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl,pentyl, hexyl, heptyl, 2,4,4-trimethylpentyl, 2-ethylhexyl, octyl,nonyl, decyl, undecyl, dodecyl, tetradecyl, pentadecyl, hexadecyl,heptadecyl, octadecyl, nonadecyl or icosyl. Preferably, R₃₃ as alkyl isC₁–C₈alkyl.

R₃₃, R₃₄ and R₃₅ as substituted phenyl are mono- to pentasubstituted,e.g. mono-, di- or trisubstituted, in particular tri- or disubstituted,on the phenyl ring. Substituted phenyl, naphthyl or biphenyl aresubstituted e.g. with a linear or branched C₁–C₄alkyl such as methyl,ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl or t-butyl orwith a linear or branched C₁–C₄alkoxy such as methoxy, ethoxy,n-propoxy, isopropoxy, n-butoxy, isobutoxy, s-butoxy or t-butoxy,preferably with methyl or methoxy.

If R₃₃, R₃₄ and R₃₅ are an S— or N-containing 5- or 6-memberedheterocyclic ring, they are, for example, thienyl, pyrrolyl or pyridyl.

In the expression di(C₁–C₁₂alkyl)aminomethyl, C₁–C₁₂alkyl has the samemeanings as given above.

C₂–C₁₂alkenyl is linear or branched, can be mono- or polyunsaturated andis, for example, allyl, methallyl, 1,1-dimethylallyl, 1-butenyl,2-butenyl, 1,3-pentadienyl, 1-hexenyl or 1-octenyl, in particular allyl.

C₁–C₄alkylthio is linear or branched and is, for example, methylthio,ethylthio, n-propylthio, isopropylthio, n-butylthio, isobutylthio,s-butylthio or t-butylthio, preferably methylthio.

C₂–C₄alkenyl is, for example, allyl, methallyl, 1-butenyl or 2-butenyl.

Halogen is fluorine, chlorine, bromine and iodine, preferably, fluorine,chlorine and bromine.

The term polyoxaalkyl includes C₂–C₂₀alkyl interrupted by 1 to 9 O atomsand stands, for example, for structural units such as CH₃—O—CH₂—,CH₃CH₂—O—CH₂CH₂—, CH₃O[CH₂CH₂O]_(y)—, where y=1–9, —(CH₂CH₂O)₇CH₂CH₃,—CH₂—CH(CH₃)—O—CH₂—CH₂CH₃.

Preference is given to compositions in which

-   R₂₅ is hydrogen, —OCH₂CH₂—OR₂₉, morpholino, SCH₃, a group

-    or a group

-   R₂₆ is hydroxyl, C₁–C₁₆alkoxy, morpholino or dimethylamino;-   R₂₇ and R₂₈ independently of one another are C₁–C₄alkyl, phenyl,    benzyl or C₁–C₁₆alkoxy, or-   R₂₇ and R₂₈ together with the carbon atom to which they are bonded    form a cyclohexyl ring;-   R₂₉ is hydrogen or

-   R₃₀, R₃₁, and R₃₂ are hydrogen;-   R₃₃ is C₁–C₁₂alkyl, unsubstituted phenyl or phenyl substituted by    C₁–C₁₂alkyl or C₁–C₁₂alkoxy;-   R₃₄ is

-    and-   R₃₅ is phenyl which is substituted by C₁–C₄alkyl or C₁–C₄alkoxy.

Preferred compounds of the formulae VIII, IX, X, XI, XII and XIII areα-hydroxycyclohexyl phenyl ketone or2-hydroxy-2-methyl-1-phenylpropanone,(4-methylthiobenzoyl)-1-methyl-1-morpholinoethane,(4-morpholinobenzoyl)-1-benzyl-1-dimethylaminopropane, benzil dimethylketal, (2,4,6-trimethylbenzoyl)diphenylphosphine oxide,bis(2,6-dimethoxybenzoyl)-(2,4,4-trimethyl-pent-1-yl)phosphine oxide,bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide orbis(2,4,6-trimethylbenzoyl)(2,4-dipentoxyphenyl)phosphine oxide anddicyclopentadienylbis(2,6-difluoro-3-pyrrolo)titanium,methyl-phenylglyoxalate.

Preference is also given to compositions in which, in the formula VIIIR₂₇ and R₂₈ independently of one another are C₁–C₆alkyl, or togetherwith the carbon atom to which they are bonded form a cyclohexyl ring,and R₂₆ is hydroxyl.

The proportion of compounds of the formula I (photoinitiator component(b)) in the mixture with compounds of the formulae VIII, IX, X or XI(=photoinitiator component (c)) is 5 to 99%, e.g. 20–80%, preferably 25to 75%.

Also important are compositions in which, in the compounds of theformula VIII, R₂₇ and R₂₈ are identical and are methyl, and R₂₆ ishydroxyl or isopropoxy.

Likewise preferred are compositions comprising compounds of the formulaI and compounds of the formula X in which

-   R₃₃ is unsubstituted or mono- to tri-C₁–C₁₂alkyl- or    C₁–C₁₂alkoxy-substituted phenyl or C₁–C₁₂alkyl;-   R₃₄ is the group

-    or phenyl; and-   R₃₅ is phenyl substituted by one to three C₁–C₄alkyl or C₁–C₄alkoxy.

Of particular interest are compositions as described above whichcomprise photoinitiator mixtures of the formulae I, VIII, IX, X, XI, XIIor XIII and are liquid at room temperature. The preparation of thecompounds of the formulae VIII, IX, X, XI, XII and XIII is generallyknown to the person skilled in the art and some of the compounds areavailable commercially. The preparation of oligomeric compounds of theformula VIII is described, for example, in EP 161463. A description ofthe preparation of compounds of the formula IX can, for example, befound in EP 209831. The preparation of compounds of the formula X isdisclosed, for example, in EP 7508, EP 184095 and GB 2259704. Thepreparation of compounds of the formula XI is described, for example, inEP 318894, EP 318893 and EP 565488.

The photopolymerizable compositions advantageously comprise thephotoinitiator in an amount of from 0.05 to 20% by weight, e.g. 0.05 to15% by weight, preferably 0.1 to 5% by weight, based on the composition.The amount of photoinitiator stated is based on the total of all addedphotoinitiators if mixtures thereof are used, i.e. both on thephotoinitiator (b) and on the photoinitiators (b)+(c).

Compounds according to the invention in which Z₁ or Z₂ aresiloxane-containing radicals are particularly suitable asphotoinitiators for surface coatings, in particular vehicle paints.These photoinitiators are not distributed as homogeneously as possiblein the formulation to be cured, but enriched in a targeted manner on thesurface of the coating to be cured, i.e. a targeted orientation of theinitiator to the surface of the formulation takes place.

The photopolymerizable compositions can be used for various purposes,for example as printing inks, such as screen printing inks, flexographicprinting inks or offset printing inks, as clearcoats, as colour coats,as white coats, e.g. for wood or metal, as powder coatings, as paints,inter alia for paper, water, metal or plastic, as daylight-curablecoatings for marking buildings and roads, for photographic reproductionprocesses, for holographic recording materials, for image recordingprocesses or for the production of printing plates which can bedeveloped using organic solvents or aqueous-alkaline media, for theproduction of masks for screen printing, as dental filling materials, asadhesives, as pressure-sensitive adhesives, as laminating resins, asphotoresists, e.g. galvanoresists, etch or permanent resists, bothliquid and dry films, as photostructurable dielectrics, and as solderstopping masks for electronic circuits, as resists for the preparationof colour filters for any type of screen or for producing structures inthe production process of plasma displays and electroluminescencedisplays, for the production of optical switches, optical gratings(interference gratings), for the preparation of three-dimensionalobjects by mass curing (UV curing in transparent moulds) or by thestereolithography process, as is described, for example, in U.S. Pat.No. 4,575,330, for the preparation of composite materials (e.g. styrenicpolyesters which may contain glass fibres or other fibres and otherauxiliaries) and other thick-layer materials, for the coating or sealingof electronic components or as coatings for optical fibres. Thecompositions are also suitable for the preparation of optical lenses,e.g. contact lenses and Fresnel lenses, and for the preparation ofmedical instruments, auxiliaries or implants.

The photoinitiators according to present invention are also suitable foruse in compositions as coatings for optical fibers. In general, opticalfibers are coated with protective coats directly after their production.The fiber of glass is drawn and then one or more coatings are applied tothe glass string. Usually, one, two or three coats are applied, the topcoating, for example, is colored (“ink layer or ink coating”). Further,several thus coated optical fibers may be put together to a bundle andbe coated all together, i.e. cabling of the fibers. The compositionsaccording to the present invention in general are suitable for any ofthese coatings, which have to exhibit good softness over a broadtemperature range, good tensile strength and toughness and rapidUV-curing characteristics.

Each of the coats, inner primary (usually a soft coating), outer primaryor secondary (usually a harder coating than the inner coating), tertiaryor the cabling coat, may comprise at least one radiation-curableoligomer, at least one radiation curable monomer diluent, at least onephotoinitiator, and additives.

In general all radiation curable oligomers are suitable. Preferred areoligomers with a molecular weight of at least 500, for example500–10,000, 700–10,000, 1,000–8,000 or 1,000–7,000, in particularurethane oligomers, containing at least one unsaturated group.Preferably the radiation curable oligomer has two terminal functionalgroups. The coat may contain not only one specific oligomer, but alsomixtures of different oligomers. The preparation of suitable oligomersis known to the person skilled in the art and for example published inU.S. Pat. No. 6,136,880, incorporated herein by reference. The oligomersare, for example, prepared by reacting an oligomer diol, preferably adiol having 2–10 polyoxaalkylene groups, with a diisocyanate or apolyisocyanate and a hydroxy-functional ethylenically unsaturatedmonomer, e.g. hydroxyalkyl(meth)acrylate. Specific examples of each ofthe components named above, as well as suitable ratios of thesecomponents are given in U.S. Pat. No. 6,136,880, incorporated herein byreference.

The radiation curable monomer can be used in a manner to control theviscosity of the coating formulation. Accordingly, a low viscositymonomer with at least one functional group capable of photoinitiatedpolymerization is employed. The amount for example is chosen to adjustthe viscosity in a range from 1,000 to 10,000 mpas, i.e. usually forexample from 10–90, or 10–80 wt % are used. The functional group of themonomer diluent preferably is of the same kind than the one of theoligomer component, for example an acrylate or vinyl ether function anda higher alkyl or polyether moiety. Examples of monomer diluentssuitable for coating compositions for optical fibers are published inU.S. Pat. No. 6,136,880, col. 12, line 11 ff., incorporated herein byreference.

In primary coatings preferably monomers having an acrylate or vinylether functionality and a polyether moiety of 4 to 20 C atoms is used.Specific examples are given in the US patent incorporated by referenceand cited above.

The composition may also comprise a poly(sitoxane) as described in U.S.Pat. No. 5,595,820 to improve the adhesive properties of the formulationon the optical fiber glass substrate.

The coating composition usually also comprises further additives, e.g.antioxidants, light stabilizers, UV absorbers such as for example givenin the list above in particular ^(RTM)IRGANOX 1035, 1010, 1076, 1222,^(RTM)TINUVIN P, 234, 320, 326, 327, 328, 329, 213, 292, 144, 622LD (allprovided by Ciba Specialty Chemicals), ^(RTM)ANTIGENE P, 3C, FR, GA-80,^(RTM)SUMISORB TM-061 (provided by Sumitomo Chemical Industries Co.),^(RTM)SEESORB 102, 103, 501, 202, 712, 704 (provided by Sypro ChemicalCo., Ltd.), ^(RTM)SANOL LS770 (provided by Sankyo Co. Ltd.) to preventthe coloring of the coat, in particular during the processing, and toimprove the stability of the cured coat. Particularly interesting arestabilizer combinations of hindered piperidine derivatives (HALS) andhindered phenol compounds, e.g. a combination of IRGANOX 1035 andTINUVIN 292, for example in a ratio of 1:1. Further, additives are forexample wetting agents and other additives having an effect on therheology properties of the coating. Also amines, for examplediethylamine, can be added.

Other examples for additives for compositions for the coating of opticalfibers are silane coupling agents, e.g. γ-aminopropyltriethoxysilane,γ-mercaptopropyltrimethoxysilane, γ-methacryloxypropyl-trimethoxysilane,SH6062, SH6030 (provided by Toray-Dow Corning Silcone Co., Ltd.), KBE903, KBE 603, KBE 403 (provided by Shin-Etsu Chemical Co., Ltd.)

In order to prevent coloring of the coatings the compositions may alsocomprise fluorescent additives or optical brighteners, as, for example,^(RTM)UVITEX OB, provided by Ciba Specialty Chemicals.

The photoinitiators according to the present application in coatingcompositions for optical fibers can be admixed with one or more otherknown photoinitiators. These are in particular monoacylphosphine oxides,such as diphenyl-2,4,6-trimethylbenzoyl phosphine oxide;bisacylphosphine oxides, such as bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (^(RTM)IRGACURE 819),bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentyl phosphine oxide;α-hydroxyketones, such as 1-hydroxycyclohexyl phenyl ketone(^(RTM)IRGACURE 184), 2-hydroxy-2-methyl-1-phenyl-1-propanone(^(RTM)DAROCUR 1173),2-hydroxy-1-[4-(2-hydroxy-ethoxy)phenyl]-2-methyl-1-propanone(^(RTM)IRGACURE 2959); α-aminoketones, such as2-methyl-1-[4-(methylthio)phenyl]-2-(4-morpholinyl)-1-propanone(^(RTM)IRGACURE 907),2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone(^(RTM)IRGACURE 369); benzophenones, such as benzophenone,2,4,6-trimethylbenzophenone, 4-methylbenzophenone, 2-methylbenzophenone,2-methoxycarbonylbenzophenone, 4,4′-bis(chloromethyl)benzophenone,4-chlorobenzophenone, 4-phenylbenzophenone,4,4′-bis(dimethylamino)benzophenone, 4,4′-bis(diethylamino)benzophenone,methyl 2-benzoylbenzoate, 3,3′-dimethyl-4-methoxybenzophenone,4-(4-methylphenylthio)benzophenone and also ketal compounds, for example2,2-dimethoxy-1,2-diphenyl-ethanone (^(RTM)IRGACURE 651); monomeric ordimeric phenylglyoxalic acid esters, such as for example methylphenylglyoxalic acid ester or 1,2-(benzoylcarboxy)ethane. In particularsuitable are admixtures with mono- or bisacylphosphine oxides and/orα-hydroxy ketones.

It is evident that the formulations, in order to enhance the propertiesof the photoinitiators may also comprise sensitizer compounds, forexample amines.

The coatings are either applied “wet on dry” or “wet on wet”. In thefirst case after the application of the primary coat a curing step byirradiation with UV light is carried out prior to the application of thesecond coat. In the second case both coatings are applied and curedtogether by irradiation with UV light.

The curing with UV irradiation in this application usually takes placein a nitrogen atmosphere. In general all radiation sources usuallyemployed in the photocuring technique can be used for the curing ofoptical fiber coatings. These are, for example the radiation sourceslisted below Generally, mercury medium pressure lamps or/and Fusion Dlamps are used. Also flash lights are suitable. It is evident that theemission of the lamps is matched with the absorption of thephotoinitiator or photoinitiator mixture which is used. The opticalfiber coating compositions may also be cured by irradiation with anelectron beam, in particular with low power electron beams, as is, forexample disclosed in WO 98/41484.

In order to distinguish different fibers in an assembly, the fibers maybe covered with a third colored coating (“ink coating”). Thecompositions used for this coating in addition to the polymerizablecomponents and the photoinitiator comprise a pigment or dye. Examplesfor pigments suitable for optical fiber coatings are inorganic pigments,such as for example titanium dioxide, zinc oxide, zinc sulfide, bariumsulfate, aluminium silicate, calcium silicate, carbon black, black ironoxide, copper chromite black, iron oxides, chromium oxide greens, ironblue, chrome green, violet (e.g. manganese violet, cobalt phosphate,CoLiPO₄), lead chromates, lead molybdates, cadmium titanate andpearlescent and metallic pigments, as well as organic pigments, such asmonoazo pigments, di-azo pigments, di-azo condensation pigments,quinacridone pigments, dioxazine violet, vat pigments, perylenepigments, thiolndigo pigments, phthalocyanine pigments andtetrachloroisoindolinones. Examples for suitable pigments are carbonblack for a black coating, titanium dioxide for a white coating,diarylide yellow or diazo based pigments for yellow coatings,phthalocyanine blue, and other phthalocyanines for blue coatings,anthraquinone red, naphthole red, monazo based pigments, quinacridonepigments, anthraquinone and perylenes for red coatings, phthalocyaninegreen and nitroso based pigments for green coatings, monazo and diazobased pigments, quinacridone pigments, anthraquinones and perylenes fororange coatings, and quinacridone violet, basic dye pigments andcarbazole dioxazine based pigments for violet coatings. The personskilled in the art is well aware of formulating and combining suitablefurther pigments if even more colored coatings, such as aqua, brown,gray, pink etc. are needed. The mean particle size of the pigmentsusually is about 1 □m or less. The size of commercial pigments can bereduced by milling, if necessary. The pigments for example, can be addedto the formulation in the form of a dispersion in order to simplify themixing with the other ingredients of the formulation. The pigments are,for example dispersed in a low viscosity liquid, e.g. a reactivediluent. Preferred is the use of organic pigments. Suitable amounts forpigment in the ink coating are for example 1–20, 1–15, preferably 1–10wt %. The ink coating in general also comprises a lubricant to provideimproved break-out properties of the single coated optical fiber fromthe matrix. Examples of such lubricants are silicones, fluorocarbon oilsor resins and the like, preferably a silicone oil or a functionalizedsilicone compound, e.g. silicone diacrylate is used.

The compositions according to the present invention are further suitableas a matrix material for an assembly of coated optical fibers. That is,several of the primary, secondary (and in some cases tertiary) coatedfibers, for example, in the third coat being differentiated by differentcolors, are assembled in a matrix.

The coating of an assembly preferably besides the additives given abovealso contains a release agent to allow for easy access to the individualfibers during the installation of the optical fiber cables. i.e.

Examples for such release agents are teflon, silicones, siliconacrylates, fluorocarbon oils or resins and the like. The release agentssuitably are added in an amount of 0.5–20 wt %. Examples of ink coatingsand matrix materials for coated optical fibers are given in U.S. Pat.Nos. 6,197,422, 6,130,980 and EP 614099, incorporated herein byreference.

The compositions are also suitable for the preparation of gels havingthermotropic properties. Such gels are described, for example, in DE19700064 and EP 678534.

Furthermore, the compositions can be used in dry-film paints, as aredescribed, for example, in Paint & Coatings Industry, April 1997, 72 orPlastics World, Volume 54, No. 7, page 48(5).

The compounds according to the invention can also be used as initiatorsfor emulsion, bead or suspension polymerizations or as initiators of apolymerization for the fixing of ordered states of liquid-crystallinemono- and oligomers, or as initiators for the fixing of dyes to organicmaterials.

In surface coatings, mixtures of a prepolymer with polyunsaturatedmonomers are often used which also contain a monounsaturated monomer.The prepolymer here is primarily responsible for the properties of thecoating film, and variation thereof allows the person skilled in the artto influence the properties of the cured film. The polyunsaturatedmonomer functions as a crosslinking agent which renders the coating filminsoluble. The monounsaturated monomer functions as a reactive diluent,by means of which the viscosity is reduced without the need to use asolvent.

Unsaturated polyester resins are mostly used in two-component systemstogether with a monounsaturated monomer, preferably with styrene. Forphotoresists, specific one-component systems are often used, for examplepolymaleimides, polychalcones or polyimides, as are described in DE2308830.

The compounds according to the invention and mixtures thereof may alsobe used as free-radical photoinitiators or photoinitiating systems forradiation-curable powder coatings. The powder coatings may be based onsolid resins and monomers containing reactive double bonds, for examplemaleates, vinyl ethers, acrylates, acrylamides and mixtures thereof. Afree-radically UV-curable powder coating can be formulated by mixingunsaturated polyester resins with solid acrylamides (e.g. methylmethacrylamide glycolate) and with a free-radical photoinitiatoraccording to the invention, as described, for example, in the paper“Radiation Curing of Powder Coating”, Conference Proceedings, RadtechEurope 1993 by M. Wittig and Th. Gohmann. Similarly, free-radicallyUV-curable powder coatings can be formulated by mixing unsaturatedpolyester resins with solid acrylates, methacrylates or vinyl ethers andwith a photoinitiator (or photoinitiator mixture) according to theinvention. The powder coatings can also comprise binders, as described,for example, in DE 4228514 and EP 636669. The UV-curable powder coatingscan also comprise white or coloured pigments. Thus, for example,preferably rutile titanium dioxide may be used in concentrations of upto 50% by weight in order to obtain a cured powder coating with goodcoverage. The process normally involves electrostatic or tribostaticspraying of the powder onto the substrate, for example metal or wood,melting the powder by heating and, after a smooth film has formed,radiation-curing of the coating with ultraviolet or visible light, e.g.using medium-pressure mercury lamps, metal halide lamps or xenon lamps.A particular advantage of the radiation-curable powder coatings comparedwith their thermally curable counterparts is that the flow time afterthe melting of the powder particles can be extended as desired in orderto ensure the formation of a smooth, high-gloss coating. In contrast tothermally curable systems, radiation-curable powder coatings can beformulated without the desired effect of a reduction in their servicelife such that they melt at relatively low temperatures. For thisreason, they are also suitable as coatings for heat-sensitivesubstrates, for example wood or plastics.

In addition to the photoinitiators according to the invention, thepowder coating formulations can also comprise UV absorbers. Appropriateexamples have been listed above under points 1–8.

The photocurable compositions according to the invention are suitable,for example, as coating substances for substrates of all kinds, e.g.wood, textiles, paper, ceramic, glass, plastics such as polyesters,polyethylene terephthalate, polyolefins or cellulose acetate, inparticular in the form of films, and also metals such as Al, Cu, Ni, Fe,Zn, Mg or Co and Ga, As, Si or SiO₂, on which a protective coating or,for example by imagewise exposure, an image is to be applied.

The substrates can be coated by applying a liquid composition, asolution or suspension to the substrate. The choice of solvent and theconcentration depend primarily on the type of composition and on thecoating procedure. The solvent should be inert, i.e. it should notundergo any chemical reaction with the components and should be capableof being removed again after the coating operation, in the dryingprocess. Examples of suitable solvents are ketones, ethers and esters,such as methyl ethyl ketone, isobutyl methyl ketone, cyclopentanone,cyclohexanone, N-methylpyrrolidone, dioxane, tetrahydrofuran,2-methoxyethanol, 2-ethoxyethanol, 1-methoxy-2-propanol,1,2-dimethoxyethane, ethyl acetate, n-butyl acetate and ethyl3-ethoxypropionate.

Using known coating processes, the formulation is applied to asubstrate, e.g. by spincoating, dip coating, knife coating, curtaincoating, brushing, spraying, especially, for example, by electrostaticspraying and reverse-roll coating, and by electrophoretic deposition. Itis also possible to apply the photosensitive layer to a temporary,flexible support and then to coat the final substrate, e.g. acopper-laminated circuit board, by means of layer transfer vialamination.

The amount applied (layer thickness) and the type of substrate (layersupport) are dependant on the desired field of application. The suitablelayer thicknesses for the respective fields of application, e.g. in thephotoresist field, printing ink field or paint field are known to theperson skilled in the art. Depending on the field of application, thelayer thickness range generally includes values from about 0.1 μm tomore than 10 mm.

The radiation-sensitive compositions according to the invention areused, for example, as negative resists which have very highphotosensitivity and can be developed in an aqueous-alkaline mediumwithout swelling. They are suitable as photoresists for electronics,such as galvanoresists, etch resists, both in liquid and also dry films,solder stopping resists, as resists for the production of colour filtersfor any desired type of screen, or for the formation of structures inthe manufacturing process of plasma displays and electroluminescencedisplays, for the production of printing plates, for example offsetprinting plates, for the production of printing formes for typographicprinting, planographic printing, intaglio printing, flexographicprinting or screen printing formes, the production of relief copies,e.g. for the production of texts in Braille, for the production ofstamps, for use in moulding etching or use as microresists in theproduction of integrated circuits. The compositions may also be used asphotostructurable dielectrics, for the encapsulation of materials or asinsulator coating for the production of computer chips, printed circuitsand other electrical or electronic components. The possible layersupports and the processing conditions of the coated substrates arevaried accordingly.

The compounds according to the invention are also used for theproduction of single-layer or multilayer materials for image recordingor image duplication (copies, reprography), which may be monotone ormulticoloured. Furthermore, these materials can also be used as colourtesting systems. In this technology, it is also possible to useformulations which contain microcapsules and, to generate the image, athermal step can be connected downstream of the exposure step. Suchsystems and technologies and their applications are described, forexample, in U.S. Pat. No. 5376459.

For photographic information recording, films made of polyester,cellulose acetate or plastic-coated papers, for example, are used, andfor offset printing formes, specially treated aluminium, for example, isused, for the production of printed circuits, copper-faced laminates,for example, are used, and for the production of integrated circuits,silicon wafers are used. The usual layer thicknesses for photographicmaterials and offset printing forms are generally about 0.5 μm to 10 μm,and for printed circuits are from 1.0 μm to about 100 μm.

After the substrates have been coated, the solvent is usually removed bydrying, to leave a layer of the photoresist on the support.

The term “imagewise” exposure encompasses both exposure via a photomaskcontaining a predetermined pattern, for example a diapositive, exposureby a laser beam which is moved, for example under control by a computer,over the surface of the coated substrate, thereby generating an image,and irradiation with computer-controlled electron beams. It is alsopossible to use masks of liquid crystals which can be controlled pixelby pixel in order to generate digital images, as described, for example,by A. Bertsch, J. Y. Jezequel, J. C. Andre in Journal of Photochemistryand Photobiology A: Chemistry 1997, 107, p. 275–281 and by K.-P. NicolayIn Offset Printing 1997, 6, p. 34–37.

Conjugated polymers, for example polyanilines, can be converted from asemiconducting state to a conducting state by doping with protons. Thephotoinitiators according to the invention can also be used for theimagewise exposure of polymerizable compositions which contain suchpolymers in order to form conducting structures (in the irradiatedzones) which are embedded in the insulating material (unexposed zones).Such materials can, for example, be used as wiring or connectingcomponents for the production of electrical or electronic components.

Following the imagewise exposure of the material and prior to thedeveloping, it may be advantageous to carry out a thermal treatment fora relatively short period. Here, only the exposed parts are thermallycured. The temperatures used are generally 50–150° C., preferably80–130° C.; the thermal treatment time is usually between 0.25 and 10minutes.

Furthermore, the photocurable composition can be used in a process forthe production of printing formes or photoresists, as described, forexample, in DE 4013358. Herein, prior to, simultaneously with orfollowing the imagewise irradiation, the composition is briefly exposedto visible light having a wavelength of at least 400 nm without a mask.Following the exposure and the optional thermal treatment, the unexposedareas of the photoresist are removed using a developer in a manner knownper se.

As already mentioned, the compositions according to the invention can bedeveloped by aqueous-alkaline media. Suitable aqueous-alkaline developersolutions are, in particular, aqueous solutions of tetraalkylammoniumhydroxides or of alkali metal silicates, phosphates, hydroxides andcarbonates. Relatively small amounts of wetting agents or organicsolvents can also be added to these solutions. Typical organic solventswhich may be added to the developer liquids in small amounts are, forexample, cyclohexanone, 2-ethoxyethanol, toluene, acetone and mixturesof such solutions.

Photocuring is of great importance for printing inks since the dryingtime of the binder is a crucial factor for the production rate ofgraphic products and should be in the order of magnitude of fractions ofseconds. UV-curable inks are of importance particularly for screen,flexographic and offset printing.

As already mentioned, the mixtures according to the invention are alsohighly suitable for the production of printing plates. Here, mixtures ofsoluble linear polyamides or styrene/butadiene or styrene/isoprenerubber, polyacrylates or polymethyl methacrylates containing carboxylgroups, polyvinyl alcohols or urethane acrylates with photopolymerizablemonomers, for example acryl- or methacrylamides or acrylic ormethacrylic esters, and a photoinitiator, for example, are used. Filmsand plates made from these systems (wet or dry) are exposed via thenegative (or positive) of the print original, and the uncured parts aresubsequently washed out using a suitable solvent.

A further field of use for photocuring is the coating of metals, forexample the coating of metal sheets and tubes, cans or bottlecaps, andthe photocuring of plastic coatings, for example PVC-based floor or wallcoverings. Examples of the photocuring of paper coatings are thecolourless coating of labels, record sleeves or book covers.

Likewise of interest is the use of the compounds according to theinvention for the curing of mouldings made from composite materials. Thecomposite material consists of a self-supporting matrix material, e.g. aglass-fibre fabric, or else, for example, plant fibres [cf. K.-P. Mieck,T. Reussmann in Kunststoffe 85 (1995), 366–370], which is impregnatedwith the photocuring formulation. Mouldings made of composite materialsproduced using the compounds according to the invention have highmechanical stability and resistance. The compounds according to theinvention can also be used as photocuring agents in moulding,impregnation or coating materials, as described, for example, in EP7086. Such materials are, for example, fine coating resins, which aresubject to strict requirements with regard to their curing activity andyellowing resistance, fibre-reinforced mouldings, for example planar orlongitudinally or transversely corrugated light-diffusing panels.Processes for the production of such mouldings, for example hand lay-uptechniques, fibre lay-up spraying, centrifugal or winding techniques,are described, for example, by P. H. Selden in “GlasfaserverstärkteKunststoffe” [Glass-fibre-reinforced plastics], page 610, SpringerVerlag Berlin-Heidelberg-New York 1967. Examples of articles which maybe produced by this method are boats, chipboard or plywood panels coatedon both sides with glass-fibre-reinforced plastic, pipes, sportarticles, roof coverings, and containers etc. Further examples ofmoulding, impregnation and coating materials are UP resin fine coatingsfor mouldings containing glass fibres (GFP), e.g. corrugated sheets andpaper laminates. Paper laminates may be based on urea or melamineresins. The fine coating is produced on a support (e.g. a film) prior tothe production of the laminate. The photocurable compositions accordingto the invention can also be used for casting resins or for embeddingarticles, e.g. electronic components etc. Moreover, they can also beused for the lining of cavities and pipes. For curing, medium-pressuremercury lamps are used, as are customary in UV curing. However, lessintensive lamps are also of particular interest, e.g. those of the typeTL 40W/03 or TL40W/05. The intensity of these lamps correspondsapproximately to that of sunlight. It is also possible to use directsunlight for the curing. It is a further advantage that the compositematerial can be removed from the light source in a partially cured,plastic state and can be deformed. Curing is then carried out tocompletion.

The compositions and compounds according to the invention can also beused for the preparation of optical waveguides and optical switches, usebeing made of the generation of a difference in the refractive indexbetween exposed and unexposed areas.

Also important is the use of photocurable compositions for imagingprocesses and for the optical production of information carriers. Here,as already described above, the coat (wet or dry) applied to the supportis irradiated with UV or visible light via a photomask and the unexposedareas of the coat are removed by treatment with a solvent (=developer).The photocurable layer can also be applied to the metal by anelectrodeposition technique. The exposed areas are crosslinked/polymericand thus insoluble and remain on the support. Appropriate colorationproduces visible images. If the support is a metallicized layer, thenthe metal can be removed from the unexposed areas by etching afterexposure and developing, or can be strengthened by electroplating.Printed electronic circuits and photoresists can be produced in thisway.

The photosensitivity of the compositions according to the inventiongenerally ranges from 200 nm into the IR region, preferably 200 nm–600nm. Suitable radiation comprises, for example, sunlight or light fromartificial light sources. Therefore, a large number of very differenttypes of light sources can be used. Point sources and flat radiators(lamp carpets) are suitable. Examples are: carbon arc lamps, xenon arclamps, medium-pressure, high-pressure and low-pressure mercury lamps,optionally doped with metal halides (metal halogen lamps),microwave-stimulated metal vapour lamps, excimer lamps, superactinicfluorescent tubes, fluorescent lamps, incandescent argon lamps,flashlights, photographic floodlight lamps, light-emitting diodes (LED),electron beams and X-rays. The distance between the lamp and thesubstrate to be exposed according to the invention can vary depending onthe intended use and lamp type and intensity, e.g. between 2 cm and 150cm. Of particular suitability are laser light sources, e.g. excimerlasers, such as krypton F lasers for exposure at 248 nm. It is alsopossible to use lasers in the visible region. Using this method it ispossible to produce printed circuits in the electronics industry,lithographic offset printing plates or relief printing plates, and alsophotographic image recording materials.

The invention therefore also provides a process for thephotopolymerization of nonvolatile monomeric, oligomeric or polymericcompounds having at least one ethylenically unsaturated double bond,which comprises irradiating a composition as described above with lightin the range from 200 nm into the IR region, preferably 200 nm–600 nm.The invention also provides for the use of the compounds of the formulaI as photoinitiators for the photopolymerization of nonvolatilemonomeric, oligomeric or polymeric compounds having at least oneethylenically unsaturated double bond by irradiation with light in therange from 200 nm into the IR region, preferably 200 nm–600 nm.

The invention also provides for the use of the above-describedcomposition or a process for the preparation of pigmented andunpigmented surface coatings, coatings for optical fibres, glas fibercoating, printing inks, for example screen printing inks, offsetprinting inks, flexographic printing inks, powder coatings, printingplates, adhesives, dental compositions, optical waveguides, opticalswitches, colour testing systems, composite materials, glass fibre cablecoatings, screen printing stencils, resist materials, colour filters,use for the encapsulation of electrical and electronic components, forthe production of magnetic recording materials, for the production ofthree-dimensional objects using stereolithography, for photographicreproductions, and for use as image recording material, in particularfor holographic recordings, for decolouring materials, for decolouringmaterials for image recording materials, for image recording materialsusing microcapsules.

The invention likewise provides a coated substrate which has been coatedon at least one surface with a composition as described above, and alsoa process for the photographic production of relief images in which acoated substrate is subjected to imagewise exposure and then theunexposed portions are removed with a solvent. The imagewise exposurecan be carried out via a mask or by means of a laser beam. Of particularinterest here is exposure by means of a laser beam.

The examples below illustrate the invention in more detail, although itis not intended that the invention be limited to the examples. Unlessstated otherwise, parts and percentages are based, as elsewhere in thedescription and in the claims, on the weight. Wherever reference is madeto alkyl or alkoxy radicals having more than three carbon atoms withoutstating the isomer, then the n-isomers are always intended.

Preparation of the Starting Material EXAMPLE 1a Lithium(2,4,6-trimethylbenzoyl)phenylphosphine

Under argon and with the exclusion of moisture, 14.0 g of lithium (2.0mol) are introduced into 250 ml of tetrahydrofuran at room temperature.Following the addition of 1.25 g of naphthalene, 44.8 g (0.25 mol) ofdichlorophenylphosphine are added dropwise with stirring at 20–25° C.and, after stirring for 4 h, the black solution is filtered into athree-necked round flask through a frit (G2 porosity) with the exclusionof moisture and under argon as a protective gas. 47.2 g (0.258 mol) of2,4,6-trimethylbenzoyl chloride are added dropwise at room temperatureover the course of 30 minutes with stirring and cooling. Stirring for 2hours gives the title compound as a red solution in tetrahydrofuran.

³¹P-NMR δ 98.4 ppm.

EXAMPLE 1b Preparation of lithium(2,4,6-trimethylbenzoyl)isobutylphosphine

34.4 ml (0.055 mol, +10%) of butyllithium 1.6M are slowly addeddropwise, at 0° C.–10° C., to 4.5 g (0.025 mol) of isobutylphosphine(50% solution in toluene) in 30 ml of tetrahydrofuran. At the sametemperature, 4.6 g (0.025 mol) of 2,4,6-trimethylbenzoyl chloride arethen added dropwise. After warming to room temperature, the titlecompound is obtained as an orange suspension. The shift signal δ in the³¹P-NMR spectrum appears at 50 ppm, measured against CDCl₃ as reference.

Preparation of the Compounds According to the Invention EXAMPLE 2Preparation of(Phenyl-{6-[phenyl-(2,4,6-trimethyl-benzoyl)-phosphinoylmethyl]-pyridin-2-ylmethyl}-phosphinoyl)-(2,4,6-trimethyl-phenyl)-methanone

A compound of formula I wherein A is a group

-   R₁, R₂ and R₃ are methyl, R₄ and R₅ are hydrogen,-   R is phenyl,-   W is a bond,-   n is 2,-   L is ethylene interrupted by pyridin-2-yl.

A solution of 1.32 g (0.005 mol) 2,6 bis(bromomethyl)pyridine in 5 mltetrahydrofuran is added slowly at 20–30° C. to 12 ml (0.010 mol)lithium (2,4,6-trimethylbenzoyl)phenylphosphine. The reaction suspensionis heated to 60° C. and, after the mixture has been afterstirred for 24hours, it is concentrated using the Rotavap. The residue is taken up in20 ml of toluene and is treated with 2.3 g (0.02 mol) of hydrogenperoxide 30%. After the mixture has been stirred for 2 hours between20–30° C., the reaction is complete. The reaction emulsion is pouredonto water and washed with aqueous saturated sodium hydrogencarbonatesolution, then dried over magnesium sulfate and filtered. The filtrateis concentrated using the Rotavap. The residue is purified over silicagel and dried under a high vacuum. 0.4 g of the title compound areobtained as a yellow solid. Melting point: 192–193° C.

EXAMPLE 3(Phenyl-{6-[phenyl-(2,4,6-trimethyl-benzoyl)-phosphinoyl]-hexyl}-phosphinoyl)-(2,4,6-trimethyl-phenyl)-methanone

A compound of formula I wherein A is a group

-   R₁, R₂ and R₃ are methyl, R₄ and R₅ are hydrogen,-   R is phenyl,-   W is a bond,-   n is 2,-   L is hexylene.

A solution of 1,22 g (0.005 mol) 1,6 dibromohexane in 5 mltetrahydrofuran is added slowly at 20–30° C. to 12 ml (0.010 mol)lithium (2,4,6-trimethylbenzoyl)phenylphosphine. The reaction is carriedout according to Example 2.

0.2 g of the title compound are obtained as a yellow solid. Meltingpoint: 171–172° C.

EXAMPLE 4(Phenyl-{2′-[phenyl-(2,4,6-trimethyl-benzoyl)-phosphinoylmethyl]-biphenyl-2-ylmethyl}-phosphinoyl)-(2,4,6-trimethyl-phenyl)-methanone

A compound of formula I wherein A is a group

-   R₁, R₂ and R₃ are methyl, R₄ and R₅ are hydrogen,-   R is phenyl,-   W is a bond,-   n is 2,-   L is ethylene interrupted by biphenylene.

A solution of 1.70 g (0.005 mol)2,2′ bis bromomethyl[1,1′] biphenyl in 5ml tetrahydroturan is added slowly at 20–30° C. to 12 ml (0.010 mol)lithium (2,4,6-trimethylbenzoyl)phenylphosphine. The reaction is carriedout according to Example 2.

1.30 g of the title compound are obtained as a yellow solid. Meltingpoint: 116–118° C.

EXAMPLE 5({1-Methyl-4-[phenyl-(2,4,6-trimethyl-benzoyl)-phosphinoyl]-pentyl}-phenyl-phosphinoyl)-(2,4,6-trimethyl-phenyl)-methanone

compound of formula I wherein A is a group

-   R₁, R₂ and R₃ are methyl, R₄ and R₅ are hydrogen,-   R is phenyl,-   W is a bond,-   n is 2,-   L is 2,5 hexylene.

A solution of 1.22 g (0.005 mol) 2,5 dibromohexane in 5 mltetrahydrofuran is added slowly at 20–30° C. to 12 ml (0.010 mol)lithium (2,4,6-trimethylbenzoyl)phenylphosphine. The reaction is carriedout according to Example 2.

0.10 g of the title compound are obtained as a yellow solid. Meltingpoint: 167–169° C.

EXAMPLE 6({3-Methyl-5-[phenyl-(2,4,6-trimethyl-benzoyl)-phosphinoyl]-pentyl}-phenyl-phosphinoyl)-(2,4,6-trimethyl-phenyl)-methanone

compound of formula I wherein A is a group

-   R₁, R₂ and R₃ are methyl, R₄ and R₅ are hydrogen,-   R is phenyl,-   W is a bond,-   n is 2,-   L is pentylene substituted by methyl.

A solution of 1.22 g (0.005 mol) 1,5 dibromo-3methyl pentane in 5 mltetrahydrofuran is added slowly at 20–30° C. to 12 ml (0.010 mol)lithium (2,4,6-trimethylbenzoyl)phenylphosphine. The reaction is carriedout acoording to Example 2.

0,10 g of the title compound are obtained as a yellow resin.

³¹P-NMR (CDCl₃): 30.04 ppm

¹H-NMR (CDCl₃) : 7.76–7,70(m); 7.56–7.32(m); 6.59(s); 2.19–2.14(m);1.99–1.92 (m); 0.89–0.87(m).

Application Example

A UV-curable white coating is prepared by mixing

-   -   67.5 parts of polyester acrylate oligomer (^(RTM)EBECRYL 830,        UCB, Belgium)    -   5.0 parts of hexanediol diacrylate    -   2.5 parts of trimethylolpropane triacrylate    -   25.0 parts of rutile titanium dioxide (^(RTM)R-TC2, Tioxide,        France)    -   2.0 parts of the photoinitiator from Example 2, 3 and 4.

The coating is applied to a coil-coated aluminium sheet using a 100 μmslotted doctor knife and then cured. Curing is carried out by conveyingthe sample 4–6 times, on a conveyor belt which is moving at a speed of10 m/min, beneath an 80 W/cm medium-pressure mercury lamp (Hanovia,USA). The pendulum hardness is then determined in accordance with König(DIN53157) in [s]. The pendulum hardness is a measure of thethrough-curing of the composition. The higher the values, the moreeffective the curing which has been carried out. After the firstpendulum hardness determination, the sample is after-exposed underlow-pressure mercury lamps of the type TL 40W/03 (Philips; Emissionmaximum of 430 nm), and after 15 minutes and 16 hours the pendulumhardness is determined again. The final yellow index was determined inaccordance with ASTMD 1925-88.

Applica- Initiator Number of Pendulum Hardness [s] Yellow- tion frompasses at after 15 min after 16 h ness Example Example 10 m/minTL400W/03 TL400W/03 Index 7 2 6 76 136 0.54 8 3 4 112 193 0.75 9 4 4 108187 0.71

1. A compound of the formula I

(I), in which E is O or S and x is 0 or 1, A is cyclopentyl, cyclohexyl,naphthyl, biphenylyl, anthracyl or an O-, S- or N-containing 5- or6-membered heterocyclic ring, where the radicals cyclopentyl,cyclohexyl, naphthyl, biphenylyl, anthracyl or O-, S- or N-containing 5-or 6-membered heterocyclic ring are unsubstituted or substituted byhalogen, C₁–C₄alkyl or C₁–C₄alkoxy; or A is a group

 wherein R₁ and R₂ independently of one another are C₁–C₂₄alkyl, OR₁₁,CF₃ or halogen; R₃, R₄ and R₅ independently of one another are hydrogen,C₁–C₂₄alkyl, OR₁₁ or halogen; or two of the radicals R₁, R₂, R₃, R₄ orR₅ together form C₂–C₁₂alkylene, which can be interrupted by O, S orNR₁₄; R is C₁–C₂₄alkyl, unsubstituted or substituted byC₃–C₂₄cycloalkyl, C₃–C₂₄cycloalkenyl, phenyl, CN, C(O)R₁₁, C(O)OR₁₁,C(O)N(R₁₄)₂, OC(O)R₁₁, OC(O)OR₁₁, N(R₁₄)C(O)N(R₁₄), OC(O)NR₁₄,N(R₁₄)C(O)OR₁₁, halogen, OR₁₁, SR₁₁ or N(R₁₂)(R₁₃); C₂–C₂₄alkyl which isinterrupted once or more than once by nonconsecutive O, S or NR₁₄ andwhich is unsubstituted or substituted by phenyl, OR₁₁, SR₁₁,N(R₁₂)(R₁₃), CN, C(O)R₁₁, C(O)OR₁₁, or C(O)N(R₁₄)₂; C₂–C₂₄alkenyl whichis uninterrupted or interrupted once or more than once by nonconsecutiveO, S or NR₁₄ and which is unsubstituted or substituted by OR₁₁, SR₁₁,N(R₁₂)(R₁₃), or C₁–C₁₂alkyl; C₅–C₂₄cycloalkenyl which is uninterruptedor interrupted once or more than once by non-consecutive O, S or NR₁₄and which is unsubstituted or substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), orC₁–C₁₂alkyl; C₇–C₂₄arylalkyl which is unsubstituted or substituted onthe aryl group by C₁–C₁₂alkyl, C₁–C₁₂alkoxy or halogen; C₄–C₂₄cycloalkylwhich is uninterrupted or interrupted once or more than once by O, S orNR₁₄ and which is unsubstituted or substituted by OR₁₁, SR₁₁,N(R₁₂)(R₁₃), or C₁–C₁₂alkyl; C₈–C₂₄arylcycloalkyl orC₈–C₂₄arylcycloalkenyl; or; R is a group of the formula

wherein R₆, R₇, R₈, R₉ and R₁₀ independently of one another arehydrogen, C₁–C₂₄alkyl; C₂–C₂₄alkyl which is interrupted once or morethan once by nonconsecutive O, S or NR₁₄ and which is unsubstituted orsubstituted by OH, SH; SR₁₁ or N(R₁₂)(R₁₃), OR₁₁, phenyl or halogen; Wis —CO—O— or —CO—N(R₁₅)—; L is a di-tri-or tetravalent linking group, nis a number of 2,3 or 4; R₁₁ is hydrogen, C₁–C₂₀alkyl, C₂–C₂₀alkenyl,C₃–C₈cycloalkyl, phenyl unsubstituted or substituted by one or moreC₁–C₄alkyl, benzyl or C₂–C₂₀alkyl which is interrupted once or more thanonce by O or S and which is unsubstituted or is substituted by OH or SH;R₁₂ and R₁₃ independently of one another are hydrogen, C₁–C₂₀alkyl,C₃–C₈cycloalkyl, phenyl unsubstituted or substituted by one or moreC₁–C₄alkyl, benzyl or C₂–C₂₀alkyl which is interrupted once or more thanonce by nonconsecutive O atoms and which is unsubstituted or substitutedby OH or SH; or R₁₂ and R₁₃ together are C₃–C₅alkylene which isuninterrupted or interrupted by O, S or NR₁₄; R₁₄ is hydrogen, phenylunsubstituted or substituted by one or more C₁–C₄alkyl, C₁–C₁₂alkyl orC₂–C₁₂alkyl which is interrupted once or more than once bynonconsecutive O or S atoms and which is unsubstituted or substituted byOH or SH; R₁₅ is hydrogen, C₁–C₂₀alkyl, phenyl unsubstituted orsubstituted once or more with C₁–C₄alkyl.
 2. A compound of the formula Iaccording to claim 1 in which A is a group

 wherein E is O or S and x is 0 or 1, R₁ and R₂ independently of oneanother are C₁–C₁₂alkyl, OR₁₁, CF₃ or halogen; R₃, R₄ and R₅independently of one another are hydrogen, C₁–C₁₂alkyl, OR₁₁ or halogen;R is C₁–C₁₂alkyl, unsubstituted or substituted by phenyl, CN, OR₁₁,C(O)R₁₁, C(O)OR₁₁, C(O)N(R₁₄)₂; C₂–C₁₂alkyl which is interrupted once ormore than once by nonconsecutive O and which is unsubstituted orsubstituted by phenyl, CN, OR₁₁, C(O)R₁₁, C(O)OR₁₁, C(O)N(R₁₄)₂;C₂–C₁₂alkenyl which is uninterrupted or interrupted once or more thanonce by nonconsecutive O and which is unsubstituted or substituted byOR₁₁, N(R₁₂)(R₁₃), or C₁–C₁₂alkyl; benzyl; C₄–C₈cycloalkyl which isuninterrupted or interrupted once or more than once by O, S or NR₁₄ andwhich is unsubstituted or substituted by OR₁₁, SR₁₁, N(R₁₂)(R₁₃), orC₁–C₁₂alkyl; C₈–C₁₂arylcycloalkyl; or; R is a group of the formula

wherein R₆, R₇, R₈, R₉ and R₁₀ independently of one another arehydrogen, C₁–C₁₂alkyl; OR₁₁, phenyl or halogen; W is —CO—O— or—CO—N(R₁₅)—; L is a di-or trivalent linking group, n is a number of 2 or3; R₁₁ is hydrogen, C₁–C₁₂alkyl, C₅–C₆cycloalkyl, phenyl or benzyl; R₁₂and R₁₃ independently of one another are hydrogen, C₁–C₁₂alkyl, phenyl,benzyl or C₂–C₁₂alkyl which is interrupted once or more than once bynonconsecutive O atoms and which is unsubstituted or substituted by OHor SH; or R₁₂ and R₁₃ together are piperidino, morpholino or piperazino;R₁₄ is hydrogen, phenyl, C₁–C₁₂alkyl or C₂–C₁₂alkyl which is interruptedonce or more than once by nonconsecutive O atoms and which isunsubstituted or substituted by OH or SH; R₁₅ is hydrogen, C₁–C₁₂alkyl,phenyl unsubstituted or substituted once or more with C₁–C₄alkyl.
 3. Aprocess to prepare the compounds of formula I according to claim 1, byreacting compounds of formula II

wherein M is Li, Na or K, with a linking compound Hal-L-[Hal]_(m) orHal-W-L-[W-Hal]_(m) wherein m is 1, 2 or 3 and oxidising thecorresponding phosphines (x=0).
 4. A photocurable composition comprising(a) at least one ethylenically unsaturated photopolymerizable compoundand (b) at least one compound of the formula I according to claim 1 asphotoinitiator.
 5. A photocurable composition according to claim 4,comprising, in addition to components (a) and (b), furtherphotoinitiators (c) or further additives (d).
 6. A photocurablecomposition as claimed in claim 5, comprising, as further photoinitiator(c), at least one compound of the formula VIII, IX, X, XI, XII, XIII ormixtures thereof,

in which R₂₅ is hydrogen, C₁–C₁₈alkyl, C₁–C₁₈alkoxy, —OCH₂CH₂—OR₂₉,morpholino, SCH₃, a group

 or a group

n has a value from 2 to 10; G₁ and G₂ independently of one another areend-groups of the polymeric unit, in particular hydrogen or CH₃; R₂₆ ishydroxyl, C₁–C₁₆alkoxy, morpholino, dimethylamino or—O(CH₂CH₂O)_(m)—C₁–C₁₆alkyl; R₂₇ and R₂₈ independently of one anotherare hydrogen, C₁–C₆alkyl, phenyl, benzyl, C₁–C₁₆alkoxy or—O(CH₂CH₂O)_(m)—C₁–C₁₆alkyl, or R₂₇ and R₂₈ together with the carbonatom to which they are bonded form a cyclohexyl ring; where R₂₆, R₂₇ andR₂₈ are not all C₁–C₁₆alkoxy or —O(CH₂CH₂O)_(m)—C₁–C₁₆alkyl at the sametime, and m is a number from 1–20; and R₂₉ is hydrogen,

 or

R₃₀ and R₃₂ independently of one another are hydrogen or methyl; R₃₁ ishydrogen, methyl or phenylthio, where the phenyl ring of the phenylthioradical is unsubstituted or substituted by C₁–C₄alkyl in the 4-, 2-,2,4- or 2,4,6-position; R₃₃ and R₃₄ independently of one another areC₁–C₂₀alkyl, cyclohexyl, cyclopentyl, phenyl, naphthyl or biphenyl,where these radicals are unsubstituted or are substituted by halogen,C₁–C₁₂alkyl or C₁–C₁₂-alkoxy, or R₃₃ is an S- or N-containing 5- or6-membered heterocyclic ring, or are

R₃₅ is cyclohexyl, cyclopentyl, phenyl, naphthyl or biphenyl, theseradicals being unsubstituted or substituted by halogen, C₁–C₄alkyl orC₁–C₄alkoxy, or R₃₅ is an S— or N-containing 5- or 6-memberedheterocyclic ring; R₃₆ and R₃₇ independently of one another areunsubstituted cyclopentadienyl or cyclopentadienyl substituted once,twice or three times by C₁–C₁₈alkyl, C₁–C₁₈alkoxy, cyclopentyl,cyclohexyl or halogen; and R₃₈ and R₃₉ independently of one another arephenyl which is substituted in at least one of the two ortho positionsrelative to the titanium-carbon bond by fluorine atoms or CF₃, and whichon the aromatic ring may contain, as further substituents, unsubstitutedpyrrolinyl or pyrrolinyl substituted by one or two C₁–C₁₂alkyl,di(C₁–C₁₂alkyl)aminomethyl, morpholinomethyl, C₂–C₄alkenyl,methoxymethyl, ethoxymethyl, trimethylsilyl, formyl, methoxy or phenyl;or polyoxaalkyl, or R₃₈ and R₃₉ are

R₄₀, R₄₁, and R₄₂ independently of one another are hydrogen, halogen,C₂–C₁₂alkenyl, C₁–C₁₂alkoxy, C₂–C₁₂alkoxy interrupted by one to four Oatoms, cycylohexyloxy, cyclopentyloxy, phenoxy, benzyloxy, unsubstitutedphenyl or phenyl substituted by C₁–C₄alkoxy, halogen, phenylthio orC₁–C₄-alkylthio; or biphenyl, where R₄₀ and R₄₂ are not both hydrogen atthe same time and in the radical

 at least one radical R₄₀ or R₄₂ is C₁–C₁₂alkoxy, C₂–C₁₂alkoxyinterrupted by one to four O atoms, cyclohexyloxy, cyclopentyloxy,phenoxy or benzyloxy; E, is O, S or NR₄₃; and R₄₃ is C₁–C₈alkyl, phenylor cyclohexyl, R₄₄ is H, C₁–C₁₂alkyl, C₁–C₁₂alkyl interrupted once ormore than once by nonconsecutive O, C₅–C₁₀cycloalkyl, benzyl or phenyl;R₄₅ is C₁–C₁₂alkylene, C₄–C₈-alkenylene, C₄–C₈alkynylene, cyclohexylene,C₄–C₄₀alkylene interrupted one or more times by —O—, —S— or —NR₄₆—, oris phenylene, or R₄₅ is a group selected from

R₄₆ is hydrogen, C₁–C₁₂alkyl or phenyl.
 7. A process for thephotopolymerization of nonvolatile monomeric, oligomeric or polymericcompounds having at least one ethylenically unsaturated double bond,which comprises irradiating a composition according to claim 4 withlight in the range from 200 nm into the IR region.
 8. A coaled substratewhich has been coated on at least one surface with a compositionaccording to claim
 4. 9. A process to prepare the compounds of formulaI′

in which E is O or S and x is 0 or 1, A is cyclopentyl, cyclohexyl,naphthyl, biphenylyl, anthracyl or an O-, S- or N-containing 5- or6-membered heterocyclic ring, where the radicals cyclopentyl,cyclohexyl, naphthyl, biphenylyl, anthracyl or O-, S- or N-containing 5-or 6-membered heterocyclic ring are unsubstituted or substituted byhalogen, C₁–C₄alkyl or C₁–C₄alkoxy; or A is a group

 wherein R₁ and R₂ independently of one another are C₁–C₂₄alkyl, OR₁₁,CF₃ or halogen; R₃, R₄ and R₅ independently of one another are hydrogen,C₁–C₂₄alkyl, OR₁₁ or halogen; or two of the radicals R₁, R₂, R₃, R₄ orR₅ together form C₂–C₁₂alkylene, which can be interrupted by O, S orNR₁₄; R is a group of the formula

wherein R₆, R₇, R₈, R₉ and R₁₀ independently of one another arehydrogen, C₁–C₂₄alkyl; C₂–C₂₄alkyl which is interrupted once or morethan once by nonconsecutive O, S or NR₁₄ and which is unsubstituted orsubstituted by OH, SH; SR₁₁ or N(R₁₂)(R₁₃), OR₁₁, phenyl or halogen; Wis a bond, L is a di-tri-or tetravalent linking group, n is a number of2,3 or 4; R₁₁ is hydrogen, C₁–C₂₀alkyl, C₂–C₂₀alkenyl, C₃–C₈cycloalkyl,phenyl unsubstituted or substituted by one or more C₁–C₄alkyl, benzyl orC₂–C₂₀alkyl which is interrupted once or more than once by O or S andwhich is unsubstituted or is substituted by OH or SH; R₁₂ and R₁₃independently of one another are hydrogen, C₁–C₂₀alkyl, C₃–C₈cycloalkyl,phenyl unsubstituted or substituted by one or more C₁–C₄alkyl, benzyl orC₂–C₂₀alkyl which is interrupted once or more than once bynonconsecutive O atoms and which is unsubstituted or substituted by OHor SH; or R₁₂ and R₁₃ together are C₃–C₅alkylene which is uninterruptedor interrupted by O, S or NR₁₄; R₁₄ is hydrogen, phenyl unsubstituted orsubstituted by one or more C₁–C₄alkyl, C₁–C₁₂alkyl or C₂–C₁₂alkyl whichis interrupted once or more than once by nonconsecutive O or S atoms andwhich is unsubstituted or substituted by OH or SH; R₁₄ is hydrogen,phenyl unsubstituted or substituted by one or more C₁–C₄alkyl,C₁–C₁₂alkyl or C₂–C₁₂alkyl which is interrupted once or more than onceby nonconsecutive O or S atoms and which is unsubstituted or substitutedby OH or SH; R₁₅ is hydrogen, C₁–C₂₀alkyl, phenyl unsubstituted orsubstituted once or more with C₁–C₄alkyl, by reacting compounds offormula II

wherein M is Li, Na, K, with a linking compound Hal-L-[Hal]_(m) orHal-W-L-[W-Hal]_(m) wherein m is 1, 2 or 3 and oxidising thecorresponding phosphines (x=0).